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Il patrimonio archeologico come strumento di tutela del paesaggio storico e di sviluppo sostenibile. L’insediamento tardoantico e medievale di Hykkara in c.da San Nicola a Carini: conoscenza, tutela e valorizzazione.
No full textLa presente tesi, sviluppata nell'ambito del Dottorato in Scienze della Cultura e parte del programma “Dottorati su Tematiche Green”, approfondisce il ruolo del patrimonio archeologico come strumento di tutela del paesaggio storico e di promozione dello sviluppo sostenibile. Il caso studio analizzato è l’insediamento tardoantico e medievale di Hykkara, sito in contrada San Nicola a Carini, che viene indagato attraverso un approccio multidisciplinare basato su metodi territoriali e topografici. Nell’ambito della ricerca, l’analisi storica e archeologica - che prevede lo studio dei reperti, della cartografia storica e le ricognizioni sistematiche - è stata integrata con le moderne tecniche di indagine, quali prospezioni geofisiche e utilizzo del GIS, con l’obiettivo di comprendere le trasformazioni del paesaggio nel tempo e individuare strategie per la sua tutela. Particolare attenzione è riservata alla continuità insediativa e alle sue implicazioni ambientali, con un focus sulla gestione delle risorse naturali, la viabilità storica e il rapporto tra l’uomo e l’ambiente. In linea con gli obiettivi di sostenibilità, il lavoro propone un modello di valorizzazione del sito archeologico e del territorio circostante, che integra ricerca scientifica, conservazione e fruizione pubblica. La tesi si pone l’obiettivo di offrire elementi utili alla definizione di strumenti di tutela del paesaggio storico in chiave sostenibile, evidenziando il valore del patrimonio culturale quale strumento di rigenerazione territoriale e sensibilizzazione ambientale.This dissertation, developed within the PhD program in Cultural Sciences and as part of the "Green Thematic Doctorates" initiative, explores the role of archaeological heritage as a tool for safeguarding historical landscapes and promoting sustainable development. The case study focuses on the Late Antique and Medieval settlement of Hykkara, located in the rural area known as San Nicola in territory of Carini, examined through a multidisciplinary approach based on territorial and topographic methods. The historical and archaeological analysis - which includes the study of artifacts, historical cartography, and systematic field surveys - has been integrated with modern investigative techniques, such as geophysical prospections and the use of GIS. The aim is to understand the landscape transformations over time and identify strategies for its preservation. Special attention is given to settlement continuity and its environmental implications, with a focus on the management of natural resources, historical mobility networks, and the relationship between human activity and the environment. Aligned with sustainability objectives, this work proposes a model for enhancing the archaeological site and its surrounding territory, integrating scientific research, conservation, and public accessibility. The dissertation aims to contribute valuable insights for the development of sustainable strategies for historical landscape preservation, emphasizing cultural heritage as a means of territorial regeneration and environmental awareness
Time Domain Investigation of Dynamic ON-Resistance and Trapping Effects in GaN-on-Si HEMTs under Rectangular Gate Voltage Pulses
No full textWe present experimental results of GaN-on-Si
enhancement-mode HEMTs operated in switching mode
with resistive load, using rectangular 0-5 V gate voltage
(VGS) pulses, focusing on the investigation of charge
carriers trapping and their effects on dynamic
ON-resistance (RON). Single pulse transient measurements
indicate that current collapse related to trapping effects are
more evident for a low drain current (ID) of 100mA, while
they are strongly reduced for ID=750mA where release is
more effective. Studying the device behaviour with multiple
VGS pulses reveals a decrease in RON with pulse number
with a steady state reached after 100 ms, also confirmed by
measurement with a square wave VGS at much longer times
up to 30 min. Longer single pulses of 30 min duration allow
us to measure the DC RON that is at least a factor of ten
smaller than the one for short single and multiple pulses,
demonstrating that current collapse vanishes at longer
times. Additionally, an OFF-state stress test at VDS=55 V
reveal the presence and impact of surface/interface traps in
the drain access region, leading to an increase of 4 times in
RON in respect to pristine devices
Antimicrobial actions of zinc oxide microcrystals: from design... to ‘’ziotape’’
No full textZnO is a versatile material exhibiting reconfigurable morphologies and significant antibacterial activity towards gram positive and negative microorganisms, connected with their high surface to volume ratio and their physicochemical properties. Several models are suggested for explaining the mechanisms of bacterial growth inhibition for nanostructured ZnO, leveraging electrostatic interactions between ZnO and cell walls affecting bacterial cell integrity, release of antimicrobial Zn2+ ions, which is connected to accumulation of ZnO into bacteria cells and finally ROS formation [1]. However, ZnO nanoparticles are usually detrimental to cell viability, so new ZnO based synthetic strategies are needed to better control the ZnO biocidal effects.
To bridge this knowledge gap, in this work, we engineered a new synthetic approach based on the wet synthesis of ZnO to exploit experimental design allowing for improving synthesis yield (obtained at temperatures < 90 °C) [2], photocatalysis efficiency and the antibacterial properties of the microcrystals. The resulting ZnO-based microcrystals stabilized in a biocompatible amino-functionalized cellulose solid supports or microcrystalline matrices matrix allow for a prolonged (>24 hours) antibacterial activity based on dual mechanical/chemical routes. In the former, a direct disruptive mechanical interaction occurs with bacteria due to impaling with asymmetrical functionalized ZnO diffusing from the cellulose in presence of external stimuli (fuel or light) [3], that facilitate their motion and interaction with bacteria. For the latter, the zinc release in solution might modify the zinc homeostasis, leading to reactive oxygen species (ROS). Antimicrobial assays are carried out with two reference strains (Escherichia coli and Staphylococcus aureus) with different structural/physiological features, highlighting both the time and concentration dependency of ZnO microcrystals in killing bacteria.
Showing the technological relevance of the research, we also demonstrate the scalability of this approach towards antibacterial products dispersed in cellulose matrix and we present it as Ziotape, antimicrobial modulable ZnO-based adhesive patches to be applied on surfaces. These "smart" supports incorporate antibacterial properties that might allow to reduce the use of antimicrobials, disinfectants, drugs or creams. Currently we are carrying out experiments
trying to elucidate the antibacterial mechanisms of ZnO microcrystals: in fact, besides a direct disruptive mechanical interaction with bacteria due to ZnO particles diffusion from the cellulose in presence of external stimuli (fuel or light), also the zinc release in solution might be critical modifying the zinc homeostasis and leading to reactive oxygen species (ROS). Electrostatic interactions between ZnO microparticles and cell walls affecting bacterial cell integrity have been also described [4,5].
References:
[1] T. Vitasovic, G. Caniglia, N. Eghtesadi, M. Ceccato, E.D. Bo̷jesen, U. Gosewinkel, G. Neusser, U. Rupp, P. Walther, C.Kranz, E.E. Ferapontova, ACS Applied Materials & Interfaces 2024, 16(24), 30847-30859. DOI:10.1021/acsami.4c04682
[2] V. Errico, G. Arrabito, E. Fornetti, C. Fuoco, S. Testa, G. Saggio, S. Rufini, S. Cannata, A. Desideri, C. Falconi, C. Gargioli, ACS Applied Materials & Interfaces 2018, 10(16), 14097-14107. DOI:10.1021/acsami.7b19758
[3] G. Arrabito, G. Prestopino, P.G. Medaglia, V. Ferrara, G. Sancataldo, G. Cavallaro, F. Di Franco, M. Scopelliti, B. Pignataro, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2024, 698, 134526. DOI:10.1016/j.colsurfa.2024.134526
[4] R. Brayner, R. Ferrari-Iliou, N. Brivois, S. Djediat, M.F. Benedetti, F. Fiévet Nano Letters 2006, 6(4), 866-870. DOI:10.1021/nl052326h
[5] N. Jones, B. Ray, K.T. Ranjit, A.C. Manna, FEMS Microbiology Letters, 2008, 279(1), 71–76. DOI:10.1111/j.1574-6968.2007.0101
Optimization of Viscoelastic Tuned Mass Damper Systems Subjected to Coloured Excitations
Get PDFIn recent decades, there has been growing interest in innovative vibration control strategies to improve the structural reliability of buildings and civil structures against earthquakes, windstorms and other dynamic excitations. One of the most effective methods for reducing dynamic responses is the implementation of tuned mass dampers (TMDs), which leverage the interaction between primary and secondary subsystems. Most optimization procedures in the literature use a Kelvin–Voigt (KV) link to model this interaction. Still, when frequency-dependent devices like viscoelastic dampers and isolation bearings are involved, more refined models should be adopted. This paper extends existing optimization approaches by using the standard linear solid (SLS) model to more accurately represent the connection between the dynamic absorber and the primary structure. We also emphasize the importance of accounting for the damping in the primary system, which is often overlooked but can significantly affect the overall primary–secondary dynamic interaction. Additionally, we explore the sensitivity of optimal TMD parameters to multi-chromatic excitations, which are typically neglected, using the Kanai–Tajimi model to simulate realistic seismic accelerograms. To validate our approach, we performed time-history analyses on lumped-mass models using a selection of natural seismic events, comparing the uncontrolled configurations with KV- and SLS-type TMDs. Our results demonstrate that incorporating the frequency content of seismic inputs is crucial for optimizing the structural control system and show the potential and the effectiveness of our analytical/numerical strategy in facing general viscoelastic TMD design problems considering any kind of seismic excitatio
Plasticità e patosofia. Identità narrativa, schema motorio e metodo biografico fra Weizsäcker e Malabou
No full textThe subject of the contribution is the relationship between the concept of plasticity developed by Catherine Malabou, especially in its eaning of “destructive plasticity”, and Viktor von Weizsäcker’s reflection on the “pathic”, from the writings of the 1920s dedicated to medical anthropology and the refoundation of a relational metaphysics, up to the complete elaboration of a pathosophy.
Both for the German physician and thinker and for the French philosopher, the intertwining of the question of the living being, the form and the rearticulation of narrative identity leads to outcomes capable of profoundly questioning our time. A particular in-depth analysis is dedicated to the dislocation of narrative identity with specific reference to some examples of contemporary narration both with reference to the critical work of W.G. Sebald, and through a specific survey relating to Scandinavian literatures, between the poetry of Inger Christensen – now inscribed in the canon of those literatures – and the very recent experiments in the writing of Naja Marie Aidt
Effectiveness and safety of adjunctive cenobamate in people with focal-onset epilepsy: Interim results after 24-week observational period from the BLESS study
Get PDFObjective: Cenobamate is an antiseizure medication (ASM) with a dual mechanism of action that was recently approved for the treatment of focal seizures in adults. This analysis aimed to describe the outcomes at 12 and 24 weeks after starting cenobamate therapy in a real-world setting. Methods: BLESS [NCT05859854] is an ongoing, observational, retrospective and prospective cohort study to evaluate the real-world effectiveness and safety of adjunctive cenobamate in adults with uncontrolled focal epilepsy. Subgroup analysis was performed in subjects with 2 to 3 previous ASMs (early users) and those with >3 previous ASMs (late users). Results: The second interim analysis of the BLESS study included 388 participants with a median (interquartile range) age of 43.0 (31.0-54.0) years. They had a median of 6.0 (4.0-9.0) prior ASMs and a median of 7.2 (3.0-20.6) monthly seizures at baseline. The median monthly seizure frequency was reduced by 59.9% (19.2%-87.3%) from baseline to 24 weeks; 229 (59.0%) subjects had a >= 50% seizure frequency reduction, and 44 (11.3%) showed sustained seizure freedom. The proportion of participants taking <= 2 concomitant ASMs increased from 217 (56.5%) at baseline to 239 (65.7%) at 24 weeks. Among the early users (n = 76, 19.6%), the median reduction in monthly seizure frequency at 24 weeks was 78.0% (50.0-97.1%), and 76.3% of subjects had a >= 50% response rate. The frequency of adverse drug reactions (ADRs) was 5.3% and 23.4% in early and late users. The most frequent ADRs were somnolence, dizziness, and balance disorder; after the occurrence of ADRs, 63.5% of participants maintained the prescribed dose, and 5.2% permanently discontinued treatment. Significance: Cenobamate was effective in reducing seizure frequency in a real-world setting and showed a manageable safety profile. The treatment with cenobamate also reduced the burden of concomitant ASMs in both early and late users
“Calcium-Phosphorus-Magnesium Axis” and the Metabolic Issue of Newborns Undergoing Parenteral Nutrition: Is It Time to Change Our Perspectives?
Get PDFBackground: In recent years, progress in the field of care has made prematurity an increasingly frequent phenomenon. The premature newborn, due to incompetence, is often subjected to parenteral nutrition (PN) for prolonged periods, and there may be several complications associated with it, first and foremost metabolic complications. Methods: In particular, the aim of this study was to evaluate how specific risk factors and/or auxological parameters influenced plasma variations in calcium, phosphorus, and magnesium levels. This is because, although little analyzed in the past, these electrolytes are essential for limiting the onset of unfavorable outcomes in neonatal age. This retrospective observational study was conducted by accessing the site intranet of the University Hospital "P. Giaccone" of Palermo, recruiting all newborns with PN necessities (106 in a total of 191), admitted to NICU in the period between 1 January 2020 and 1 January 2023. Infants undergoing PN through a central venous catheter (CVC), who remained in situ for a period >= 72 h, admitted to the NICU for the first time, were included. Infants with congenital malformations and/or deceased and/or transferred and/or without CVC or with CVC who remained in situ for a period < 72 h were excluded. We thus obtained 35 newborns in 2020, 33 newborns in 2021, and 38 newborns in 2022. Results: Hypophosphatemia was associated with a lower weight percentile (average 34.8 degrees C vs. 50.8 degrees C; p = 0.02) and a longer duration of PN (average 34.6 days vs. 17.3 days; p = 0.002). Newborns with hypercalcemia had, on average, lower gestational age (average 31.6 weeks vs. 35.7 weeks; p = 0.049) and weight at birth (average 1586 g vs. 2520 g; p = 0.038). Newborns with hypermagnesemia had, on average, higher weight and length (average weight percentile 62.1 degrees C vs. 42.7 degrees C; p = 0.038; average length percentile 66.7 degrees C vs. 44.4 degrees C; p = 0.003). Among the risk factors, cesarean section and undergoing surgery most influence the serum trend of the analyzed electrolytes. Conclusions: Although our results are partial and preliminary and have not always reached statistical significance, it is clear that dyselectrolytemias, in the context of metabolic complications PN-related, must be re-evaluated and carefully examined by the clinician. Prospective and controlled trials are needed to confirm our data, i.e., that the "calcium-phosphorus-magnesium axis" no longer plays only the niche role that was previously believed
E4PED: Evidence-Based Approaches to Prevent Early School Leaving in Southern Italy
No full textThe Evidence 4 Preventing Early School Dropout (E4PED) project addresses the critical issue of early school leaving in Southern Italian regions, where dropout rates significantly exceed both national averages and European targets. This multidimensional research initiative, conducted by three research units from the Universities of Cagliari, Palermo, and Salerno, integrates international evidence synthesis with a contextual understanding of Southern Italy's educational landscape. The project combines systematic evidence synthesis, regional contextual analysis, and the development of a targeted professional development program for lower secondary school teachers. Through an Educational Design Research approach, the project aims to bridge the gap between global evidence and local practices, creating a foundation for more effective educational interventions in contexts with high early school leaving rates
Math and School Anxiety: Comparing Students with and without SLD and the Potential Role of Active Breaks
Get PDFL’ansia scolastica e l’ansia da matematica può ostacolare l’apprendimento, soprattutto negli studenti con DSA, che faticano nell’ambito delle funzioni esecutive e regolazione emotiva. L’articolo, basato sul progetto PRIN PNRR 2022 “Didattica inclusiva per migliorare l’apprendimento della matematica e ridurre l’ansia da matematica: efficacia delle pause attive in classe”, analizza dati di 4150 studenti in Sicilia, Puglia e Piemonte, confrontando ansia scolastica e da matematica tra studenti con e senza DSA. Si esplorano le pause attive come strategia inclusiva per ridurre l’ansia e supportare l’apprendimento della matematica.School and math anxiety can hinder learning, especially in students with SLD, who often struggle with Executive Functions and emotion regulation. This paper, based on data from the PRIN PNRR 2022 “Inclusive didactic for enhancing math learning and reducing math anxiety: efficacy of active breaks in the classroom” project, analyzes anxiety traits in a sub-sample of 4150 students from Sicily, Puglia, and Piedmont, comparing SLD and non-SLD students. It also explores Active Breaks as an inclusive strategy to reduce anxiety and support math learning