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Over the last years, automotive industries drove a great amount of research in the field of advanced combustion techniques minimizing carbon dioxide emissions. The so-called Low-Temperature Combustions (LTC), characterized by the self-ignition of highly premixed air-fuel mixtures, represent a promising solution to achieving high efficiency and ultralow emissions of nitrogen oxides (NOx) and particulate matter. Among these, gasoline Partially Premixed Combustion (PPC), obtained through the high-pressure direct injections of gasoline, showed a good potential for the simultaneous reduction of pollutants and emissions in compression ignited engines. However, when multiple injections per cycle are performed (with hydraulic-assisted needle opening), combustion stability might be compromised by the wave effects in the hydraulic system, which produce incoherence between the requested and injected fuel. This work presents a model-based pressure waves reconstruction strategy, based on a control-oriented model of the high-pressure common rail injection system fueled with gasoline. To determine the hydraulic system's behavior during the injection process, a specifically designed flushing bench with a high-frequency acquisition system has been developed. Experimental activities have been carried out to highlight fuel pressure fluctuations with single and double injection patterns. Through the analysis of the acquired data, the key parameters (characteristic of the system) have been identified and the accuracy of pressure waves reconstruction has been evaluated, always returning errors lower than 2% between measured and estimated instantaneous pressures. Different fuel types, injectors, and rail positions have been tested to highlight the robustness of the approach. Based on the instantaneous pressure trace estimated with the control-oriented model, a fuel quantity Fluctuation Correction Strategy (FQC), implementable on a standard engine Electronic Control Unit (ECU), has been developed. The obtained results confirm the potential to reduce fuel quantity oscillations in multiple-injections systems.

The paper offers a contribution to the study of Lilibeo’s figured vases, which make extensive use of added color. The examination of some contexts allows us to clarify the old idea of a derivation of the Lilibetane vases from the workshops of Lipari, due to a displacement of artisans who would operate first in Lipari and then in Lilibeo (like the Swans Painter). It is not completely excludes the movement of craftsmen due to destructions or political changes. However it reconstructs complex interactions in which a main role had to play the influence and the action of medium exercised by the same imported artifacts (Lipari vases, mainly, but not only).

Durability tests of thermal protection system (TPS) materials for space vehicles is of paramount importance in developing TPS materials. The limits of the presently used techniques and the need for higher accuracy and precision demand new reliable and more sensitive measurement methods. In this paper we present the validation of a new on-line and non intrusive technique to estimate the TPS material recession rate which exploits the surface layer implantation of radioactive Be-7 ions and the measurement of its characteristic gamma-rays during the recession test.

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein1 and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals.

The reaction Be(p7,γ)8B plays an important role in the Sun, where it determines the high energy component of the solar neutrino spectrum. The importance of this reaction triggered several experiments over the last decades. A combined analysis of their results produces an overall consistent picture for the energy dependence of the cross section, while an inflation of the quoted uncertainties is needed to accommodate the observed discrepancy in the absolute scale of the different data sets. The origin of this discrepancy needs to be understood for a reliable estimate of the astrophysical rate of Be(p7,γ)8B and its uncertainty. In addition, there is a question about possible common systematic effects, considering that all measurements performed so far share the same experimental approach, i.e. an intense proton beam impinging on a Be7 radioactive target. A direct measurement using a radioactive Be7 ion beam on a pure hydrogen gas target has been since long envisioned as a way to improve the situation. First attempts showed the feasibility of an experiment based on the use of a recoil mass separator to collect reaction products with high efficiency, but failed to reach a useful statistical significance because of the low beam intensity. Here we present the results obtained using the intense Be7 beam available at the Tandem Accelerator Laboratory at CIRCE, University of Campania, Italy coupled to the recoil mass separator ERNA in the energy range Ecm=367 to 812 keV. Our results are compatible only with a part of previous measurements, in particular those indicating a low value of the astrophysical S-factor at zero energy S17, thus exacerbating the discrepancy between existing measurements. The analysis of our data together with the results of previous data provides an estimate S17(0)=20.0±0.8 eV⋅b, where systematic uncertainties are inflated to obtain a statistically compatible data set.

The paper aims to reassess the entire architectural and archaeological evidence of the southern part of the sanctuary of Zeus Olympios. This includes the oikos near the SE corner of the big temple (with two building phases dated respectively to the mid-6th century and to the first half of the 5th century), and the area with a large pool and two halls located to the south. This is equipped with a complex drainage system connected with two big cisterns. All these structures can now be referred to as a coherent building program carried out from 480 to 450 B.C. The monumentality of the buildings and infrastructures reflects a grandeur of the rituals that has not been previously addressed. Until now, most scholars have focused only on the colossal Temple of Zeus, and the sanctuary was not perceived as a whole. On the contrary, it was a structured and organic ensemble that could fulfil the multiple needs of religious and festive occasions. At the same time, it engaged in dialogue with the other components of the ‘sacred acropolis’, from the ‘Herakles Temple’ to the sanctuaries to the west. As for the rites and cults practiced in this area, the findings related mainly to the last phase of usage of the sacellum suggest a female divinity, with a sphere of activities linked to female maturation. The large swimming pool and the adjoining open-air area were an integral part of these rituals. To the same group of structures belongs the next monumental hall; a stone structure facing the main entrance (a big kline or trapeza) suggests the performance of theoxenic rituals. It is an intriguing coincidence that Pindar describes how the Tyndaridae were honoured with a special emphasis by the same Teron, to whom the project of the Zeus Olympios sanctuary can be attributed.

Interventi sulle relazioni con aggiornamenti ulteriori sulle problematiche offerte dai crateri di alcuni contesti funerari della Sicilia.

A seguito delle ricerche idell’Università degli studi di Palermo, si propone una nuova lettura d’insieme dell’area sacra situata sul margine meridionale della città di Akragas, finora percepita sostanzialmente attraverso i templi monumentali più noti (Olympieion e cosiddetto Tempio di Ercole) ma in realtà frutto di una complessa sequela di interventi di infrastrutturazione e riconfigurazione monumentale, legati all’evoluzione socio-politica e alla crescita economico-materiale della città dal suo sorgere alla conquista romana. Following research by the University of Palermo, a new overview of the sacred area located on the southern edge of the city of Akragas is proposed, so far perceived substantially through the best-known monumental temples (Olympieion and so-called Temple of Hercules) but in reality the result of a complex sequence of interventions of infrastructure and monumental reconfiguration, linked to the socio-political evolution and the economic-material growth of the city from its rise to the Roman conquest.

Il contributo prende in considerazione i crateri-cinerari figurati restituiti dalle necropoli greche di Sicilia, ricollegati, in via di ipotesi, a credenze escatologiche connesse alla sfera del culto dionisiaco, cercando di rintracciare l’origine e di inquadrare l’affermarsi di tale rito in Sicilia, e di delineare gli attori di questo rituale, con il quale l’identità del/della defunto/a era richiamata dalla forma del cinerario e dalle immagini che lo decoravano. L’analisi prende avvio dai cinerari con raffinate e complesse scene mitiche dell’Agrigento dell’età della tirannide emmenide per arrivare ai crateri della Lipara del IV secolo, che esprimono attraverso narrazioni più esplicite l’auspicio (o la certezza) di un accesso a una dimensione salvifica e di felicità eterna, di un accoglimento post mortem nel thiasos divino. Si ricostruisce una pluralità di segni e mezzi espressivi variamente declinati che arricchisce di sfumature e articola il contesto socio-culturale di riferimento e il relativo panorama rituale nello spazio e nel tempo, pur in un comune sottofondo di credenze escatologiche, maturate e cresciute probabilmente nella Sicilia delle tirannidi, e sviluppatesi poi in maniera originale ma coerente nei singoli contesti, nei diversi tessuti sociali, nella trama delle differenti ritualità funerarie nel secolo successivo e oltre, quando il mito perderà a poco a poco la sua funzione legittimante e identitaria, soppiantato da narrazioni più dichiaratamente misteriche e iniziatiche. The contribution takes into consideration the figured cinerary craters returned from the Greek necropolises of Sicily, linked, by way of hypothesis, to eschatological beliefs connected to the sphere of the Dionysian cult, trying to trace the origin and to frame the affirmation of this rite in Sicily, and to outline the actors of this ritual, with which the identity of the deceased was recalled by the shape of the cinerary and by the images that decorated it. The analysis starts from the cineraries with refined and complex mythical scenes of Agrigento from the age of the emmenid tyranny to arrive at the craters of Lipara of the fourth century, which express through more explicit narratives the hope (or the certainty) of access to a saving dimension and eternal happiness, of a post mortem acceptance in the divine thiasos. A plurality of variously declined signs and expressive means is reconstructed that enriches with nuances and articulates the socio-cultural context of reference and the relative ritual panorama in space and time, albeit in a common background of eschatological beliefs, probably matured and grown in Sicily tyrannies, and then developed in an original but coherent way in the individual contexts, in the different social tissues, in the plot of the different funeral rituals in the following century and beyond, when the myth gradually loses its legitimizing and identity function, supplanted by narratives more openly mysterious and initiatory.

L’identificazione della porta ad mare ferens, ricordata da Livio per le vicende della conquista romana di Agrigento nel 211/0 a.C., ha costituito uno degli argomenti di maggior interesse per gli studiosi della topografia della città, in connessione con la localizzazione dell’agorà-foro e del non lontano tempio di Eracle/Ercole. Nel quindicennio scorso ha prevalso l’ipotesi, avanzata da G. Tripodi nel 2003, che la porta principale di collegamento con la costa sia da ubicare a Est (attuale giardino di Villa Aurea) e non già ad Ovest (sito della cosiddetta Porta Aurea) del Tempio A/ cosiddetto Tempio di Eracle; da ultimo, V. Caminneci e G. Cucchiara hanno invece rivalutato l’importanza anche del varco posto tra il Tempio di Eracle e la fascia a Sud dell’Olympieion, sede tradizionale della “Porta Aurea”, per il collegamento con il territorio e l’emporio. Sulla scorta delle indagini in corso da parte dell’Università di Palermo in questo settore della Collina dei Templi, viene qui proposta una revisione complessiva delle evidenze, che consente di definire le fasi principali di sviluppo e trasformazione di questa parte della città, in cui si inseriscono e si definiscono i connotati delle architetture militari, in relazione al contesto santuariale e, dopo la dismissione delle aree sacre a fine IV sec. a.C., alla preminente funzione assunta da questa zona nella difesa e quindi nella relazione tra la città ellenistico-romana, il territorio e il mare. So far, researchers paid special attention to the identification of the porta ad marem ferens quoted by ancient sources, and linked to the localization of the agora/forum and of the near Temple of Herakles/Hercules. In recent years, G. Tripodi’s hypothesis has prevailed, that identifies the main gate towards the sea (Porta IV) near the E side of the socalled Temple of Herakles (in the garden of Villa Aurea), rather than on the W side (in the site of the alleged Porta Aurea). Lastly, V. Caminneci and G. Cucchiara proposed a reappraisal of the role of the “Porta Aurea” as the main outlet towards the coastal emporium. Based on the new data from the current investigations by the team of the University of Palermo in the area between the temples of Zeus Olympios and Herakles, the paper re-examines all the evidences at disposal and aims to define the phases and the historical development of the fortifications in this part of the ancient town. These are considered in relationship with the sanctuary and, after the dismissal of the sacred areas at the end of the 4th century B.C., with the defense needs of the city; and finally, with the need of connection between the urban core of the Hellenistic-Roman town, the countryside and the sea.