Archivio istituzionale della ricerca - Alma Mater Studiorum Università di Bologna
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Modular Multi-level Converter Model for the Analysis, the Design and the Optimization of DC Power Systems Involving Superconducting Power Cables Cooled by Liquid Hydrogen
Get PDFDC power transmission technologies have achieved significant advancements, gaining widespread adoption within modern electrical systems. The use of superconducting cables in Magnesium Diboride (MgB2) cooled by liquid hydrogen (LH2) could drastically increase the performance of DC grids, enabling higher power transport capacity and extending transmission distance, while reducing energy loss and land occupation. Today, the transport of DC electrical energy is enabled through modular muti-level converters (MMCs) capable of effectively controlling currents, voltages and power flow. Designing an optimal DC power system, along with appropriate superconducting cable design and protection apparatus, needs accurate, yet simplified, models of the converters. This study presents simplified models that apply during the fault, able to adapt to any pre-fault scenario without a need to implement complex control systems. The developed model can be easily integrated, along with a model of a superconducting MgB2 cable, in EMT power system simulators for analysing their mutual interaction during faults and for optimizing the cable design and its protection system
Exploring algorithms to select candidates for non-selective beta-blockers in cirrhosis: A post hoc analysis of the PREDESCI trial
Get PDFBackground & Aims: Whether non-invasive tests (NITs) can accurately select patients with cirrhosis requiring non-selective beta-blockers (NSBBs) for clinically significant portal hypertension (CSPH) and prevention of decompensation is unclear. Our aim was to test the performance of NIT-based algorithms for CSPH diagnosis using the prospective PREDESCI cohort. We investigated whether a new algorithm combining NITs with endoscopy could improve performance. Methods: We included patients with compensated cirrhosis and available liver elastography who were screened during the trial. The performance of models based on liver stiffness measurement (LSM) and platelet count was evaluated. An algorithm considering endoscopy for patients with inconclusive results (the “grey zone”) was then developed and validated in an independent cohort of 195 patients in whom spleen stiffness was also available. Results: We included 170 patients from the PREDESCI cohort. An LSM ≥25 kPa alone (Baveno VII criteria) or combined with an LSM >20 kPa plus thrombocytopenia (AASLD criteria) ruled-in CSPH with positive predictive values of 88% and 89%, respectively. However, 37%-47% patients fell into the grey zone while at high risk of decompensation or death. Performing endoscopy in inconclusive cases identified patients with varices that, when reclassified as high-risk for CSPH, significantly reduced the grey zone to 22%. In this algorithm, 86% of patients with CSPH were correctly classified as high risk. The diagnostic performance was confirmed in the external validation cohort, where combining Baveno VII criteria with spleen stiffness showed similar accuracy to the model using endoscopy. Conclusions: Algorithms based only on LSM and platelet count are suboptimal to identify NSBB treatment candidates. Performing endoscopy in patients with indeterminate findings from NITs improved diagnostic performance and risk stratification. Endoscopy may be substituted by spleen stiffness for stratifying risk in the grey zone. Impact and implications: The PREDESCI trial demonstrated that non-selective beta-blockers prevent decompensation in patients with clinically significant portal hypertension (CSPH). Still, it is unclear whether we can select treatment candidates using non-invasive tests to assess the presence of CSPH without measuring HVPG (hepatic venous pressure gradient). In the prospective cohort of patients screened during the PREDESCI trial, we showed that algorithms based on liver stiffness and platelet count had suboptimal performance, mainly due to a high rate of indeterminate results. Performing endoscopy on patients in the grey zone significantly increased the number correctly characterized as having CSPH and improved the risk stratification for decompensation or death on long-term follow-up. These findings were validated in an independent cohort. In addition, a model using spleen stiffness instead of endoscopy showed similar diagnostic performance in the external validation cohort, suggesting that adequate risk stratification to select treatment candidates can be achieved with a fully non-invasive algorithm
Il Noli me tangere del Maestro del Codice di San Giorgio
No full textLa piccola tavola con il soggetto del "Noli me tangere" presenta una singolare fusione iconografica tra l'episodio di Maria Maddalena e l'incontro con i due angeli, con una lettura innovativa dell'episodio evangelico. Sebbene la definizione di tale scelta iconografica non sia stata ampiamente studiata, è evidente l'influenza di Giotto e la comparazione con altre opere coeve, come quelle della cappella Pontano ad Assisi. La scena è ambientata in un giardino rigoglioso, rispecchiando l'associazione di Cristo con un "hortulanus" (giardiniere). Il dipinto, donato nel 1888 a Firenze dall'antiquario Louis Carrand, faceva parte di un complesso polittico portatile per la devozione personale, insieme ad altre tavole conservate al Bargello e nel Metropolitan Museum di New York. Sebbene inizialmente attribuito ad Ambrogio Lorenzetti, il dipinto è ora riconosciuto come opera di un artista legato alla cosiddetta tradizione miniaturistica fiorentina, Maestro del Codice di San Giorgio, databile alla prima metà del Trecento. L'eleganza stilistica e la raffinatezza delle figure, nonché la delicata ambientazione del giardino, pongono l'opera nel contesto cosmopolita della curia avignonese, segnando un'evoluzione nel percorso artistico dell'autore
Usefulness of a TDM-Guided Approach for Optimizing Teicoplanin Exposure in the Treatment of Secondary Bloodstream Infections Caused by Glycopeptide-Susceptible Enterococcus faecium
Get PDF: To assess the clinical usefulness of teicoplanin optimized by means of a therapeutic drug monitoring (TDM)-guided approach for treating secondary bloodstream infections (BSIs) caused by Enterococcus faecium. Hospitalized patients having in the period 1 March 2021-31 October 2024 a documented BSI caused by glycopeptide-susceptible Enterococcus faecium being treated with teicoplanin as definitive targeted therapy optimized by means of a real-time TDM-guided expert clinical pharmacological advice (ECPA) program were retrospectively included. Teicoplanin trough concentrations (Cmin) ranging from 20 to 30 mg/L were defined as the desired target of efficacy based on international guidelines. Univariate analysis was performed for assessing variables potentially associated with microbiological failure (defined as persistence at the infection site of the index Enterococcus faecium strain after more than 7 days from starting treatment as documented by follow-up blood cultures). Overall, 67 patients (median age 70 years; male 55.2%) were included. Catheter-related BSIs (50.7%) and intrabdominal/biliary tract (29.9%) infections were the main sources of Enterococcus faecium BSI. The desired target of teicoplanin Cmin was attained in 62.7% of patients at the first TDM assessment and significantly increased to 85.1% (p = 0.003) at subsequent TDM-guided ECPA instances during the overall treatment course. Microbiological eradication was obtained in 95% of cases (63/67). In the univariate analysis, failing effective source control was the only variable associated with an increased risk of microbiological failure (75.0% vs. 12.7%; p = 0.01). Targeted TDM-guided teicoplanin therapy, coupled with effective source control of the primary infection site by granting microbiological eradication in the vast majority of cases, may be considered a reasonable strategy for managing glycopeptide-susceptible Enterococcus faecium secondary BSIs
La guerra dei droni e «il campo della battaglia»
No full textDopo una genealogia dell'oggeto drone- icona delle guerre del XXI secolo - si analizza il suo utilizzo nella guerra ucraina considerando come ha cambiato la funzione del campo della battaglia e le categorie di nemico/amico civile/militare. Infatti, la resistenza ucraina ha strategicamente tramutato il campo della battaglia in una territorialità digitalizzata sottraendo il corpo geopolitico dello Stato alla presa degli alti comandi russi. Sul piano del tempo invece, i droni hanno agito nello iato tra il regime di istantaneità delle connessioni e quello della materiale lentezza dei mezzi in movimento. In una simile territorialità il corpo sociale viene ricompreso in quella che viene definita la «growing civilianisation of the digital battlefield». Da un lato, questo implica la micidiale sospensione della discriminazione giuridica tra combattenti e non combattenti estendendo potenzialmente lo statuto di target anche alla totalità dei civili – salta insomma la già fragile cornice giuridica che istituisce la categoria di violenza regolare e irregolare. Dall’altro, si sostanzia la possibilità di creare una pluralità di territori digitali e connessioni strategiche in cui continuare l’attacco. L’utilizzo dei droni e l’inattesa «kill web» ucraina riescono a garantire, almeno nella prima fase del conflitto, il carattere di caccia asimmetrica
A Novel Transdiagnostic Approach to the Prevention of Eating Disorders Using Virtual Reality: Preliminary Evaluation of the H.O.M.E. Intervention
Get PDF“Virtual reality” (VR) has been used effectively in clinical psychology to improve existing treatments and prevention protocols for many psychopathologies, including eating disorders (EDs). However, no VR software was developed to concurrently tackle dysfunctional eating behaviours and three third wave cognitive–behavioural transdiagnostic factors linked to EDs: psychological inflexibility, emotion dysregulation and experiential avoidance. This preliminary study is aimed at evaluating potential effects of a new VR-based preventive intervention (H.O.M.E.—How to Observe and Modify Emotions) in improving selected outcomes of transdiagnostic factors and dysfunctional eating behaviours in the general population (GP) with ED risk compared to a waiting list (WL). N = 40 GP participants with ED risk were screened (using the SCOFF and Eating Disorder Examination Questionnaire (EDE-Q)) and randomised into VR (n = 20) or WL (n = 20) groups. Before and after intervention and at 3- and 6-month follow-up, participants completed EDE-Q, Difficulties in Emotion Regulation Scale—brief version (DERS-16) for emotion dysregulation, Acceptance and Action Questionnaire II (AAQ-II) for psychological inflexibility and Multidimensional Psychological Flexibility Inventory (MPFI) experiential avoidance scale. H.O.M.E. improved scores in all EDE-Q subscales (EDE-Q-total: p = 0.003; EDE-Q-restraint: p = 0.028; EDE-Q-eating concerns: p = 0.035; EDE-Q-shape concerns: p = 0.003; EDE-Q-weight concerns: p = 0.023), AAQ-II (p = 0.005), DERS-16-total (p = 0.006), DERS-16-difficulty in engaging in goal-directed behaviours (p = 0.008), and DERS-16-limited access to emotion regulation strategies (p = 0.001), with results greater than WL and maintained at follow-ups. Results showed potential for H.O.M.E. to represent a feasible tool to prevent EDs. Given the similarity between VR and technologies used in everyday life, H.O.M.E. may help in engaging young individuals with ED risk towards psychological support before ED onset
I rapporti di lavoro sportivo nel tennis
No full textIl contributo analizza la disciplina dei rapporti di lavoro sportivo, con particolare attenzione al tennis, partendo dalla regolamentazione del lavoro sportivo professionistico e dilettantistico nella l. n. 91/1981 per poi approfondire l'analisi della distinzione tra professionismo e dilettantismo e la nozione di lavoratore sportivo nel d.gls. 36/2021
Process-driven design of cloud data platforms
Get PDFData platforms are state-of-the-art solutions for implementing data-driven applications and analytics. They
facilitate the ingestion, storage, management, and exploitation of big data. Data platforms are built on top of
complex ecosystems of services answering different data needs and requirements; such ecosystems are offered
by different providers (e.g., Amazon AWS and Microsoft Azure). However, when it comes to engineering data
platforms, no unifying strategy and methodology is available yet, and the design is mainly left to the expertise
of practitioners in the field. Service providers simply expose a long list of interoperable and alternative engines,
making it hard to select the optimal subset without a deep knowledge of the ecosystem. A more effective
design approach starts with knowledge of the data transformation and exploitation processes that the platform
should support. In this paper, we sketch a computer-aided design methodology and then focus on the selection
of the optimal services needed to implement such processes. We show that our approach lightens the design of
data platforms and enables an unbiased selection and comparison of solutions even through different service
ecosystems
La raccolta dei dati e la costruzione dei corpora
Get PDFUno degli obiettivi del progetto Univers-ITA è stato la creazione di strumenti
che possano restituire una fotografia attendibile ed empiricamente solida
della lingua effettivamente usata da studenti e studentesse nella redazione
di testi formali all’università. Nello specifico, nell’ambito del progetto sono
stati realizzati tre corpora, Univers-ITA, Univers-ITA-ProGior e Univers-ITAProUniv,
che riproducono tre tipologie di testi redatti da studenti e studentesse
universitari con diversi corredi di metadati1. I tre corpora, che verranno
descritti nel dettaglio nelle prossime sezioni di questo contributo, sono consultabili
in accesso aperto sulla piattaforma NoSketch Engine a questo indirizzo:
https://corpora.ficlit.unibo.it/CUSP.
Per le modalità di consultazione dei corpora si rimanda al vademecum
riportato sul sito del progetto: https://site.unibo.it/univers-ita/it/corpora
Euclid preparation. LXII. Simulations and non-linearities beyond Lambda cold dark matter. 1. Numerical methods and validation
Get PDFTo constrain cosmological models beyond ACDM, the development of the Euclid analysis pipeline requires simulations that capture the non-linear phenomenology of such models. We present an overview of numerical methods and N-body simulation codes developed to study the non-linear regime of structure formation in alternative dark energy and modified gravity theories. We review a variety of numerical techniques and approximations employed in cosmological N-body simulations to model the complex phenomenology of scenarios beyond ACDM. This includes discussions on solving non-linear field equations, accounting for fifth forces, and implementing screening mechanisms. Furthermore, we conduct a code comparison exercise to assess the reliability and convergence of different simulation codes across a range of models. Our analysis demonstrates a high degree of agreement among the outputs of different simulation codes, typically within 2% for the predicted modification of the matter power spectrum and within 4% for the predicted modification of the halo mass function, although some approximations degrade accuracy a bit further. This provides confidence in current numerical methods of modelling cosmic structure formation beyond ACDM. We highlight recent advances made in simulating the non-linear scales of structure formation, which are essential for leveraging the full scientific potential of the forthcoming observational data from the Euclid mission