The Grand Sobolev Homeomorphisms and Their Measurability Properties

Abstract We study the validity of the condition (N) of Lusin for homeomorphisms under minimal assumptions on the integrability of Df. It turns out that the role of grand Sobolev spaces W1,n) and Wb 1,n) is crucial. A discussion of bi-Sobolev maps in the plane and their connections with degenerate elliptic PDEs is provided

On BV homeomorphisms

We obtain the rectifiability of the graph of a bounded variation homeomorphism $f$ in the plane and relations between gradients of $f$ and its inverse. Further, we show an example of a bounded variation homeomorphism $f$ in the plane which satisfies the $(N)$ and $(N^{-1})$ properties and strict positivity of Jacobian of both itself and its inverse, but neither $f$ nor $f^{-1}$ is Sobolev

Redefinition of the Ligurian Units at the Alps–Apennines junction (NW Italy) and their role in the evolution of the Ligurian accretionary wedge: constraints from mélanges and broken formations

We document that the undifferentiated chaotic Ligurian Units of the Monferrato–Torino Hill sector (MO-TH) at the Alps–Apennines junction consist of three different units that are comparable with the Cassio, Caio and Sporno Units of the External Ligurian Units of the Northern Apennines. Their internal stratigraphy reflects the character of units deposited in an ocean–continent transition (OCT) zone between the northwestern termination of the Ligurian–Piedmont oceanic basin and the thinned passive margin of Adria microcontinent. The inherited wedge-shaped architecture of this OCT, which gradually closed toward the north in the present-day Canavese Zone, controlled the Late Cretaceous–early Eocene flysch deposition at the trench of the External Ligurian accretionary wedge during the oblique subduction. This favoured the formation of an accretionary wedge increasing in thickness and elevation toward the SE, from the MO-TH to the Emilia Northern Apennines. Our results therefore provide significant information on both the palaeogeographical reconstruction of the northwestern termination of the Ligurian–Piedmont oceanic basin and the role played by inherited along-strike variations (stratigraphy, structural architecture and morphology) of OCT zones in controlling subduction–accretionary processes

Atomic decompositions, two stars theorems, and distances for the Bourgain-Brezis-Mironescu space and other big spaces

Given a Banach space E with a supremum-type norm induced by a collection of operators, we prove that E is a dual space and provide an atomic decomposition of its predual. We apply this result, and some results obtained previously by one of the authors, to the function space B introduced recently by Bourgain, Brezis, and Mironescu. This yields an atomic decomposition of the predual B∗ , the biduality result that B∗0=B∗ and B∗∗=B , and a formula for the distance from an element f∈B to B0

Noncanonical sortase-mediated assembly of pilus type 2b in group B Streptococcus

Group B Streptococcus (GBS) expresses 3 structurally distinct pilus types (1, 2a, and 2b) identified as important virulence factors and vaccine targets. These pili are heterotrimeric polymers, covalently assembled on the cell wall by sortase (Srt) enzymes. We investigated the pilus-2b biogenesis mechanism by using a multidisciplinary approach integrating genetic, biochemical, and structural studies to dissect the role of the 2 pilus-2b-associated Srts. We show that only 1 sortase (SrtC1-2b) is responsible for pilus protein polymerization, whereas the second one (Srt2-2b) does not act as a pilin polymerase, but similarly to the housekeeping class A Srt (SrtA), it is involved in cell-wall pilus anchoring by targeting the minor ancillary subunit. Based on its function and sequence features, Srt2-2b does not belong to class C Srts (SrtCs), nor is it a canonical member of any other known family of Srts. We also report the crystal structure of SrtC1-2b at 1.9 Å resolution. The overall fold resembles the typical structure of SrtCs except for the N-terminal lid region that appears in an open conformation displaced from the active site. Our findings reveal that GBS pilus type 2b biogenesis differs significantly from the current model of pilus assembly in gram-positive pathogens.-Lazzarin, M., Cozzi, R., Malito, E., Martinelli, M., D'Onofrio, M., Maione, D., Margarit, I., and Rinaudo, C. D. Noncanonical sortase-mediated assembly of pilus type 2b in group B Streptococcus

Did Photosymbiont Bleaching Lead to the Demise of Planktic Foraminifer Morozovella at the Early Eocene Climatic Optimum?

The symbiont-bearing mixed-layer planktic foraminiferal genera Morozovella and Acarinina were among the most important calcifiers of early Paleogene tropical–subtropical oceans. A marked and permanent switch in the abundance of these genera is known to have occurred at low-latitude sites at the beginning of the Early Eocene Climatic Optimum(EECO), such that the relative abundance of Morozovella permanently and significantly decreased along with a progressive reduction in the number of species; concomitantly, the genus Acarinina almost doubled its abundance and diversified. Here we examine planktic foraminiferal assemblages and stable isotope compositions of their tests at Ocean Drilling Program Site 1051 (northwest Atlantic) to detail the timing of this biotic event, to document its details at the species level, and to test a potential cause: the loss of photosymbionts (bleaching). We also provide stable isotope measurements of bulk carbonate to refine the stratigraphy at Site 1051 and to determine when changes in Morozovella species composition and their test size occurred. We demonstrate that the switch in Morozovella and Acarinina abundance occurred rapidly and in coincidence with a negative carbon isotope excursion known as the J event (~53 Ma), which marks the start of the EECO.We provide evidence of photosymbiont loss after the J event from a size-restricted δ13C analysis. However, such inferred bleaching was transitory and also occurred in the acarininids. The geologically rapid switch in planktic foraminiferal genera during the early Eocene was a major evolutionary change within marine biota, but loss of photosymbionts was not the primary causal mechanism

Efficacy of a new technique - INtubate-RECruit-SURfactant-Extubate - "IN-REC-SUR-E" - in preterm neonates with respiratory distress syndrome: Study protocol for a randomized controlled trial

Background: Although beneficial in clinical practice, the INtubate-SURfactant-Extubate (IN-SUR-E) method is not successful in all preterm neonates with respiratory distress syndrome, with a reported failure rate ranging from 19 to 69 %. One of the possible mechanisms responsible for the unsuccessful IN-SUR-E method, requiring subsequent re-intubation and mechanical ventilation, is the inability of the preterm lung to achieve and maintain an "optimal" functional residual capacity. The importance of lung recruitment before surfactant administration has been demonstrated in animal studies showing that recruitment leads to a more homogeneous surfactant distribution within the lungs. Therefore, the aim of this study is to compare the application of a recruitment maneuver using the high-frequency oscillatory ventilation (HFOV) modality just before the surfactant administration followed by rapid extubation (INtubate-RECruit-SURfactant-Extubate: IN-REC-SUR-E) with IN-SUR-E alone in spontaneously breathing preterm infants requiring nasal continuous positive airway pressure (nCPAP) as initial respiratory support and reaching pre-defined CPAP failure criteria. Methods/design: In this study, 206 spontaneously breathing infants born at 24+0-27+6 weeks' gestation and failing nCPAP during the first 24 h of life, will be randomized to receive an HFOV recruitment maneuver (IN-REC-SUR-E) or no recruitment maneuver (IN-SUR-E) just prior to surfactant administration followed by prompt extubation. The primary outcome is the need for mechanical ventilation within the first 3 days of life. Infants in both groups will be considered to have reached the primary outcome when they are not extubated within 30 min after surfactant administration or when they meet the nCPAP failure criteria after extubation. Discussion: From all available data no definitive evidence exists about a positive effect of recruitment before surfactant instillation, but a rationale exists for testing the following hypothesis: a lung recruitment maneuver performed with a step-by-step Continuous Distending Pressure increase during High-Frequency Oscillatory Ventilation (and not with a sustained inflation) could have a positive effects in terms of improved surfactant distribution and consequent its major efficacy in preterm newborns with respiratory distress syndrome. This represents our challenge. Trial registration: ClinicalTrials.gov identifier: NCT02482766. Registered on 1 June 2015

Planktic foraminiferal response to the early Eocene climatic perturbations: the post-PETM hyperthermals and the EECO event

Obiettivo di questa ricerca è l’indagine di alcuni episodi di riscaldamento estremo a breve e lunga durata dell’Eocene inferiore associati a profonde variazioni del ciclo del Carbonio e condizioni paleooceanografiche: ipertermali e Early Eocene Climatic Optimum (EECO). A tal fine sono state selezionate tre successioni eoceniche di mare profondo da diversi contesti paleoceanografici: dalle basse latitudini, la sezione della Tetide centro occidentale del Terche (Italia nord orientale) e il Site Atlantico occidentale ODP 1051 (Blake Nose) dalle medie latitudini il Site Atlantico sud orientale ODP 1263 (Walvis Ridge). Questi casi-studio sono stati affrontati integrando analisi micropaleontologica e geochimica. La prima è principalmente basata sui foraminiferi planctonici, ampiamente utilizzati per studi paleoambientali poiché registrano effetti delle perturbazioni delle acque superficiali nella chimica dei gusci e nelle variazioni delle associazioni. Le indagini degli ipertermali H1 o ETM2, H2 e I1 nella sezione di Terche mostrano rilevanti cambiamenti nelle associazioni del plancton calcareo che indicano aumento di eutrofia associato a un indebolimento della stratificazione termica delle acque superficiali, sebbene le variazioni siano transitorie e più intense durante l’ETM2. Ciascun evento coincide con anomalie marnose riconducibili all’aumento della diluizione terrigena poiché gli indicatori di dissoluzione non mostrano variazioni significative. Le condizioni di perturbazione persistono anche durante la fase di recupero del ciclo del carbonio implicando tassi di ripresa più lenti per ambiente e biota. L'analisi dell’EECO nei Site atlantici rivela significativi cambiamenti nelle associazioni a foraminiferi planctonici. Il più evidente è la drastica riduzione in abbondanza e numero di specie di Morozovella e un parallelo incremento nelle abbondanze e diversificazione di Acarinina. Le possibili cause di questo turnover globale e permanente, già documentato in altre località delle basse latitudini, possono essere molteplici ed includono: temperature elevate, prolungati alti livelli di pCO2, acidificazione delle acque superficiali, perdita dei simbionti (bleaching) o competizione ecologica. Il test sui morozovellidi del Site 1051, per verificare l'ipotesi del bleaching attraverso l'analisi del segnale del δ13C, mostra evidenze di bleaching e riduzione nella dimensione dei gusci in alcune specie di Morozovella poco sopra l'evento J. Questo segnale è tuttavia transitorio ed interessa anche gli acarininidi invalidando così questa ipotesi per spiegare il calo permanente di Morozovella. Varie specie di Morozovella non recuperano la massima dimensione del guscio; ciò implica il superamento della loro soglia di optimum ecologico durante l’EECO. L’analisi della direzione di avvolgimento nei morozovellidi dei Site 1051 e 1263 evidenzia una preferenza nell’avvolgimento destrorso durante l'intervallo che precede l’EECO. Tuttavia, si osserva una prima marcata inversione verso un avvolgimento sinistrorso poco sopra il J che diviene permanente poco sopra il K/X. Incrementi temporanei delle forme sinistrorse si verificano anche durante alcuni ipertermali pre-EECO. Precedenti interpretazioni prediligono una spiegazione genetica per le inversioni dell’avvolgimento piuttosto che una risposta ecologica. Questi nuovi dati non possono convalidare o negare la prima ipotesi, ma stimolano una rinnovata considerazione della seconda. Alla base dell’EECO nel Site 1263 si registra inoltre la virtuale scomparsa dei chiloguembelinidi e la riduzione nell’abbondanza dei subbotinidi riconducibili ad una contrazione delle nicchie ecologiche dovuta all'indebolimento della stratificazione termica delle acque. Il segnale a foraminiferi planctonici sottolinea il sorprendente effetto della perturbazione di lunga durata indotta dall’EECO che si è sovrapposto ed ha prevalso sui cambiamenti effimeri legati agli ipertermali.The main goal of this research was to investigate some extreme warming episodes characterizing the early Eocene climate and related to profound variations on the global carbon cycle and paleoceanographic conditions, the short-lived hyperthermals and the long-lasted Early Eocene Climatic Optimum (EECO). To pursue this aim three early Eocene deep-sea successions were selected from different paleoceanographic settings: the low-latitude central western Tethyan Terche section (northeastern Italy) and the western Atlantic ODP Site 1051 (Blake Nose), and the mid-latitudes southeastern Atlantic ODP Site 1263 (Walvis Ridge). These case studies were approached with integrated micropaleontological and geochemical analysis. The former is mainly based on planktic foraminifera, widely employed in the study of past environments as they record the effects of surface waters perturbations both in test chemistry and changes within the assemblages. Investigation of the three hyperthermals, H1 or ETM2, H2 and I1 at the Tethyan Terche section highlights significant changes in calcareous plankton assemblages across these events, suggesting increase in surface-water eutrophication coupled with a weakening of the upper water-column thermal stratification, although these changes were transient and more intense during the ETM2. Each event coincides with lithological anomalies interpreted as essentially linked to increased terrigenous dilution, as dissolution proxies do not display significant variations. The perturbed conditions persisted during the early CIE recovery, implying slower recovery rates for the environment and biota than for the carbon cycle. The analysis of the Atlantic sites encompassing the EECO reveals major changes in planktic foraminiferal assemblages across this perturbation mainly consisting in a permanent reduction in abundance and number of species of Morozovella paralleled by increase in abundance and diversification of Acarinina. Possible causes to explain this global and permanent overturn, previously documented in other low-latitude locations, are manifold and may include the sustained elevated temperature, prolonged high level of pCO2, surface-waters acidification, loss of photo-symbionts (bleaching) or even ecological competition. A test on Morozovella species from Site 1051 was performed to verify the bleaching hypothesis through analysis of the δ13C signal. Evidences of bleaching and test-size reduction were documented in a number of Morozovella species just above the J event. Nonetheless, the bleaching signal was transient and also involved acarininids, thus invalidating this hypothesis to explain the Morozovella permanent drop. Some Morozovella species never recover their maximum test-size implying that their ecological optimum threshold was crossed during the EECO. Analysis of the Morozovella coiling direction at Sites 1051 and 1263 highlight a dominant dextral preference for this genus during the interval preceding the EECO. However, all species show a first prominent flip to sinistral coiling starting slightly above the J event that became permanent slightly above the K/X event. Temporary switches towards sinistral coiling mode also occurred during several pre-EECO hyperthermals. Previous interpretations favour genetic explanations for coiling flips rather than ecological responses. These new data cannot validate or disprove the former idea, but should stimulate renewed thought on the latter idea. Planktic foraminiferal response to the EECO at Site 1263 also includes the virtual disappearance of the chiloguembelinids and abundance reduction of the thermocline-dweller subbotinids, interpreted as a result of ecological niches contraction probably related to weakening of the upper water-column thermal stratification. The whole planktic foraminiferal signal emphasizes the striking effect of the long-lasted EECO perturbation that superimposed and prevailed on the ephemeral changes linked to the hyperthermals

Comunicazione e partecipazione per il governo del territorio

I recenti esercizi di governo del territorio, affidandosi sempre più spesso ad una stretta collaborazione pubblico-privato e a strumenti che presentano una elevata discrezionalità, pongono con urgenza la necessità di offrire una legittimazione più solida alle decisioni del piano e del progetto urbanistico e richiedono di verificarne nel tempo le ricadute sul territorio. È questo il motivo per cui la comunicazione delle ipotesi di trasformazione della città e del territorio e la costruzione intorno ad esse di processi reali di partecipazione sono oggi al centro di una estrema varietà di iniziative nel nostro Paese. Il volume passa in rassegna alcune esperienze di risalto nazionale (il Progetto “Città di Città” della provincia di Milano, il Piano Strategico e PRG di Jesi, il Piano delle Periferie di Roma, il PSC e il POC di Ravenna, e molti altri), focalizzando l’attenzione sull’evoluzione delle pratiche di comunicazione e di partecipazione applicate a tali strumenti nel tempo. Altre esperienze riguardano le regioni Marche e Abruzzo, che, sebbene in ritardo nella definizione di una riforma organica delle leggi di governo del territorio, stanno sperimentando forme d’innovazione dei piani e dei progetti urbanistici attraverso il ricorso a percorsi partecipativi che si avvalgono di sperimentate o nuove modalità di comunicazione. Lo scopo del volume non è quello di tratteggiare un modello ideale della partecipazione e della comunicazione per l’urbanistica ma di ricercare quelle linee di convergenza che possono essere in grado di migliorare la consapevolezza e l’inclusione delle politiche pubbliche anche alla luce delle nuove occasioni di coinvolgimento delle comunità locali offerte dal web e dalle tecnologie informatiche