The fluid dynamics of climate: General Circulation Models and applications to past, present and future climatic changes

La presente tesi di ricerca riguarda l’ottimizzazione e l’utilizzo di modelli climatici globali, ed in modo particolare del modello climatico globale ad alta risoluzione EC-Earth, per affrontare una serie di problemi di interesse nel contesto della dinamica del clima e del cambiamento climatico. In particolare, l’attività di ricerca ha riguardato il lavoro di ottimizzazione, ovvero di tuning, del modello climatico globale EC-Earth, appartenente alla categoria degli Earth System Models, e nello specifico della componente atmosferica del modello. Lo studio del cosiddetto “Equable Climate” dell’Eocene, un periodo caldo verificatosi circa 50 milioni di anni fa caratterizzato da una bassa differenza di temperatura tra equatore e poli e ridotto ciclo annuale alle alte latitudini. Gli “Equable Climates” sono un problema tutt’ora irrisolto nelle scienze del clima e la loro comprensione potrebbe avere importanti implicazioni circa la nostra comprensione ed interpretazione dei cambiamenti climatici in corso. L'analisi delle caratteristiche della precipitazione invernale nella regione montuosa dell’Hindu-Kush Karakoram, nell’Himalaya occidentale, e delle sue teleconnessioni, con particolare riferimento all’Oscillazione Nord Atlantica. Lo studio é stato condotto mediante l’utilizzo congiunto di dati osservativi, rianalisi atmosferiche e simulazioni climatiche realizzate con il modello EC-Earth. Lo studio del cambiamento climatico nelle regioni montane, ed in particolare della dipendenza dalla quota dell’aumento delle temperature superficiali terrestri registrato durante il corso del XX secolo e previsto per le prossime decadi (Elevation-Dependent Warming, EDW). Lo studio si é focalizzato principalmente sulla regione montuosa dell’Himalaya- Tibetan Plateau ed é stato condotto mediante l’utilizzo di un ensemble di modelli climatici globali che hanno partecipato al Coupled Model Intercomparison Project Phase 5 (CMIP5) e all’analisi dei dati osservativi disponibili

Novel Lossen rearrangement and derived non-isocyanate polyurethanes (NIPUs)

Die moderne Gesellschaft ist zur Aufrechterhaltung ihrer Wirtschaft und ihres Energieverbrauchs stark von fossilen Brennstoffen abhängig. Die weltweiten Vorräte an diesen Ressourcen gehen jedoch schnell zur Neige und haben große Auswirkungen auf die Umwelt. Daher werden für die nahe Zukunft erneuerbare und nachhaltige Technologien benötigt. Der Einfang, die Speicherung und Nutzung von CO₂, dem Hauptprodukt der Verbrennung fossiler Brennstoffe und Hauptverursacher der globalen Erwärmung, sowie die Nutzung erneuerbarer Rohstoffe sind daher von hoher Relevanz, insbesondere im Bereich der chemischen Forschung. Im ersten Teil dieser Arbeit wird die Verwendung von Kohlendioxid als Ersatz für teure und toxische Säurechloride zur Aktivierung von Hydroxamsäuren während der Lossen-Umlagerung diskutiert. Hierbei erfolgte die O-Acetylierung der Hydroxamsäure ohne Acylchloride, sondern durch Addition von CO₂ an die deprotonierte Hydroxylgruppe der Säure in einem CO₂-schaltbaren ionischen Flüssigkeitssystem (SWIL). Die Analyse der mechanistischen Aspekte der Reaktion erfolgte mittels Gaschromatographie (GC), kernmagnetischer Resonanzspektroskopie (NMR) und Online-Infrarot-Spektroskopie (IR). Im zweiten Teil dieser Arbeit wurde die Lossen-Umlagerung auch für die Synthese von erneuerbaren Carbamat-Dien-Monomeren für die Synthese von Nicht-Isocyanat-Polyurethanen (NIPUs) über Thiol-En-Polymerisation eingesetzt. Die Vorteile dieser Technik liegen nicht nur im nachhaltigeren Verfahren, sondern auch in der Nutzung der Nebenprodukte für den gleichen Zweck. Die anschließende Thiol-En-Polymerisation von nachwachsenden Carbamat- und Harnstoff-Dienen mit sowohl erneuerbaren als auch kommerziell erhältlichen Dithiolen führte zur Bildung von NIPUs mit interessanten und einstellbaren Eigenschaften. Das vorgeschlagene System ermöglicht auch die Herstellung von statistischen- und Block-Copolymeren, wodurch die Kombination von Monomereigenschaften in ein und demselben Makromolekül ermöglicht wird. Diese Fähigkeit wurde durch die Kombination verschiedener NIPU-Eigenschaften ausgenutzt, um Materialien zu erhalten, die für die Beibehaltung einer bestimmten Form und für die anschließende Analyse ihrer Zugfestigkeit durch Spannungs-Dehnungs-Experimente geeignet sind. Besonders interessante Ergebnisse lieferten NIPUs auf der Basis von Limonen und 10-Undecenoat, deren E-Modul und gummiartige Konsistenz ein großes Potenzial für Anwendungen als Elastomermaterial zeigten. Zusätzlich wurde das E-Modul des Limonen-basierten NIPU durch Zugabe von modifizierten Cellulose Nanokristalle (CNCs) erhöht. Schließlich konnten die vorgeschlagenen Thiol-EnPolymere durch H₂O₂-Oxidation der Sulfidbindungen auf einfache und nachhaltige Weise nachmodifiziert werden, was zu entsprechenden Polysulfonen mit verbesserten thermischen Eigenschaften führte

Italijanske politike sprejemanja in pandemija: Od izključenosti do zapuščenosti

The article analyzes how the COVID-19 pandemic has affected the management of reception centers for refugees and asylum seekers in Italy. By analyzing the transformation of Italian reception policies in the last years, the article shows the relationship between these changes and the condition of refugees and asylum seekers in these centers during the COVID-19 pandemic. Overcrowded housing, the absence of institutional guidance on managing the situation, and the interruption of many migrants’ migratory projects are the main findings that emerged. The article is based on digital ethnographic techniques, in addition to phone interviews with key speakers of the social contexts monitored online.Članek obravnava vpliv pandemije Covida-19 na upravljanje sprejemnih centrov za begunce in prosilce za azil v Italiji. Na podlagi analize sprememb v politiki sprejemanja v zadnjih letih prikazuje, kako so te v omenjenih centrih med pandemijo vplivale na življenjske razmere beguncev in prosilcev za azil. Rezultati analize poudarjajo predvsem prenatrpane nastanitvene zmogljivosti, odsotnost institucionalnih smernic za obvladovanje položaja, pa tudi prekinitev selitvenih načrtov številnih migrantov. Članek temelji na digitalnih etnografskih tehnikah in telefonskih intervjujih s ključnimi govorci družbenih kontekstov, ki se spremljajo na spletu

A safety review of drugs used for the treatment of retinopathy of prematurity

Retinopathy of Prematurity (ROP) is a sight-threatening disease representing one of the main disabling diseases affecting premature newborns. Presently, ROP is treated by surgical interventions and drug therapies are limited to the off-label use of a little amount of molecules approved for other pathologies

Transitions in auditory rehabilitation with bone conductive implant (bci)

Background: The bone conductive implants (BCI) are nowadays a reliable alternative for rehabilitation of specific forms of hearing loss, i.e. conductive, mixed or single sided deafness (SSD). Aims/Objective: To analyse the various factors in play when considering an auditory rehabilitation with a bone-conductive device (BCI). Materials and Methods: The clinical charts of subjects who underwent BCI application at the same Implanting Center from 2005 to 2018 were retrieved analysing also the reason for eventual explantation and the alternative option (transition) for hearing rehabilitation. Results: Nine BAHA Compact, 4 BAHA Intenso, 21 BAHA Divino, 3 BAHA BP100, 4 Ponto, 2 Sophono, 5 Bonebridge, 5 BAHA5 Attract; 11 BAHA5 Connect were used in 12 unilateral COM; 16 bilateral COM; 3 unilateral cholesteatoma; 6 bilateral cholesteatoma; 2 unilateral otosclerosis; 5 bilateral otosclerosis; 9 congenital malformations; 6 major otoneurosurgical procedures; 5 sudden deafness. Explantation was necessary for five subjects. Conclusions: Middle ear pathology and sequels from surgery represent the most common reason for BCI implantation, both in unilateral and in bilateral cases. Transition from one implantable device to another one can be predictable, mostly when explantation is necessary. Significance: The role of BCI for rehabilitation in middle ear pathology may be extremely important

Fully Renewable Non-Isocyanate Polyurethanes via the Lossen Rearrangement

In this work, a straightforward and efficient synthesis approach to renewable non‐isocyanate polyurethanes (NIPUs) is described. For this purpose, suitable and renewable carbamate monomers, possessing two double bonds, are synthesized from hydroxamic fatty acid derivatives via the Lossen rearrangement in a one‐step synthesis, and sustainable dithiols are synthesized from dialkenes derived from renewable feedstock (i.e., limonene and 1,4‐cyclohexadiene). Subsequently, the comonomers are polymerized with the highly efficient thiol–ene reaction to produce NIPUs with M$_{n}$ values up to 26 kg mol$^{−1}$ bearing thioether linkages. The main side product of the Lossen rearrangement, a symmetric urea, can also be polymerized in the same fashion. Important in the view of sustainability, the monomer mixture can also be used directly, without separation. The obtained polymers are characterized by NMR, attenuated total reflection‐infrared spectroscopy, differential scanning calorimetry, and size exclusion chromatography

Multimodality radionuclide imaging in fever of unknown origin presenting with a solitary spleen lesion

Abstract Background Fever of unknown origin (FUO) still represents a serious challenge for clinicians, since it can be related to a wide spectrum of disorders, ranging from infections to malignancies. In this scenario, nuclear medicine can be of value to achieve a correct diagnosis both through positron emission computed tomography (PET/CT) and 99mTc labeled hexamethylpropylene amine oxime (HMPAO) white blood cell (WBC) scintigraphy. Case presentation We are presenting the case of 65-year-old male, who was referred to our hospital due to prolonged unexplained fever. He was submitted to abdomen ultrasonography (US) that did not disclose relevant pathological findings. Subsequently, he underwent PET/CT scan with 18F-fluorodeoxyglucose (18F-FDG) that revealed an area of increased tracer uptake in splenic inferior pole. In order to solve differential diagnosis between tumor and infection, he was submitted to 99mTc-HMPAO WBC scintigraphy that resulted negative for sites of pathologic radiolabeled cells' accumulation but revealed a photopenic area in the splenic inferior pole. The pattern of mismatched uptake between 18F-FDG PET/CT and 99mTc-HMPAO WBC scintigraphy was considered highly suspicious for spleen tumor localization. The patient was scheduled for splenectomy and histology resulted positive for non-Hodgkin lymphoma (NHL) of diffuse large B cell type. After splenectomy, a further 18F-FDG PET/CT revealed the appearance of hypermetabolic hepatic lesions. The patient underwent chemotherapy with complete remission. Conclusion Nuclear medicine provides valuable tools for differential diagnosis in FUO. In case of patients presenting solitary lesion of the spleen, the combined use of 18F-FDG PET/CT and 99mTc-HMPAO WBC scintigraphy can provide relevant information to aid clinicians to a correct diagnosis

Italian Constitutional Court removes the prohibition on gamete donation in Italy

n/