20 research outputs found
BULLDOZING AND RESTING TRACES OF FRESHWATER MUSSEL ANODONTA WOODIANA AND SUBSTRATE CHARACTERISTICS IN LAKE-MARGIN AND RIVER SETTINGS OF UMBRIA, ITALY
The neoichnology of the freshwater mussel Anodonta (Sinanodonta) woodiana (Lea, 1834) is examined herein in some continental environments of Umbria (central Italy), such as lake-margin and river dam-margin settings. This study, based on analysis of about 200 traces, reveals that this mussel burrows employing two types of behaviours: bulldozing which produces horizontal meanders to straight bilobate traces, often filled with peloidal faecal pellets (pseudofaeces and backfill), and resting (vertical stationary into substrate) while filter feeding. A new type of very soft substrate, the âcloudgroundâ is proposed. It is placed at the water-sediment interface, above the soupground. After four years of observation, the cloudground was buried with shells and traces, preserving through the fossilization barrier about 20% of the Anodonta traces. This bivalve activity is a useful tool to recognize preservation of mud in quiet environments and parallels ichnological evidence of unknown epichnial trace fossils in the continental realm. Cloudground with resting traces must be investigated also in modern marine basin floor environments where cloud of mud dominates and considered also in geological record
Photonic Properties of Silicon-Based Materials
Non peer reviewe
SelectMDx and Multiparametric Magnetic Resonance Imaging of the Prostate for Men Undergoing Primary Prostate Biopsy: A Prospective Assessment in a Multi-Institutional Study
Prostate-specific antigen (PSA) testing as the sole indication for prostate biopsy lacks specificity, resulting in overdiagnosis of indolent prostate cancer (PCa) and missing clinically significant PCa (csPCa). SelectMDx is a biomarker-based risk score to assess urinary HOXC6 and DLX1 mRNA expression combined with traditional clinical risk factors. The aim of this prospective multi-institutional study was to evaluate the diagnostic accuracy of SelectMDx and its association with multiparametric magnetic resonance (mpMRI) when predicting PCa in prostate biopsies. Overall, 310 consecutive subjects were included. All patients underwent mpMRI and SelectMDx prior to prostate biopsy. SelectMDx and mpMRI showed sensitivity and specificity of 86.5% vs. 51.9%, and 73.8% vs. 88.3%, respectively, in predicting PCa at biopsy, and 87.1% vs. 61.3%, and 63.7% vs. 83.9%, respectively, in predicting csPCa at biopsy. SelectMDx was revealed to be a good predictor of PCa, while with regards to csPCa detection, it was demonstrated to be less effective, showing results similar to mpMRI. With analysis of strategies assessed to define the best diagnostic strategy to avoid unnecessary biopsy, SelectMDx appeared to be a reliable pathway after an initial negative mpMRI. Thus, biopsy could be proposed for all cases of mpMRI PI-RADS 4-5 score, and to those with Prostate Imaging-Reporting and Data System (PI-RADS) 1-3 score followed by a positive SelectMDx
SiOC thin films: an efficient light source and an ideal host matrix for Eu^2+ ions
The intense luminescence of SiOC layers is studied and its dependence on the parameters of the thermal annealing process elucidated. Although the emission of SiOC is bright enough to be interesting for practical applications, this material is even more promising as a host matrix for optically active Eu ions. Indeed, when incorporated in a SiOC matrix, Eu3+ ions are efficiently reduced to Eu2+, producing a very strong visible luminescence peaked at 440 nm. Eu2+ ions benefit also of the occurrence of an energy transfer mechanism involving the matrix, which increases the efficiency of photon absorption for exciting wavelengths shorter than 300 nm. We evaluate that Eu doping of SiOC produces an enhancement of the luminescence intensity at 440 nm accounting for about a factor of 15. These properties open the way to new promising perspectives for the application of Eu-doped materials in photonic and lighting technologies
Taphonomy, ichnology, and palaeoecology to distinguish event beds in varied shallow-water settings (Betic Cordillera, SE Spain)
The recognition of event beds is of paramount importance to reconstruct palaeoenvironments and to determine palaeoecological parameters. Tortonian and Tyrrhenian deposits have been studied in the Cabo de la Huerta section (Alicante, Southeastern Spain), where both open-platform and coastal deposits crop out. In the absence of sedimentary structures, we carried out ichnological, taphonomic, and palaeoecological analyses to determine the main processes involved in the materialâs sedimentation. The Tortonian beds are made up of interbedded fine-grained and coarse-grained calcarenites. Event beds are mainly signalled by the presence of Ophiomorpha nodosa in coarse-grained calcarenites, typically produced by opportunistic crustaceans just after sedimentation. Background sedimentation is represented by fine-grained calcarenites without well-preserved burrows due to the soupy consistency of the substrate. The alternance of burrow-rich and burrow-poor beds reveals a decreasing-upward frequency of storm events pointing out a deepening-upward trend. The Tyrrhenian material records a regression from a sandy beach environment to a continental backshore. A thick skeletal concentration of resedimented shells from different habitats and with different residence times on the substrate was found between the beach and backshore deposits. Its features make it recognizable as a major storm deposit where a census assemblage is mixed together with a time-averaged one. Integrated palaeontological analysis is shown to be an excellent tool in diverse environmental settings in order to differentiate event beds, in particular where clear sedimentological criteria are not available.This research was supported by the project CGL2015-66835-P, financed by the Spanish Ministry of Education and Science (MINECO, Government of Spain)
Eu^3+ reduction and efficient light emission in Eu_2O_3 films deposited on Si substrates
none7A stable Eu3+âEu2+ reduction is accomplished by thermal annealing in N2 ambient of Eu2O3 films deposited by magnetron sputtering on Si substrates. Transmission electron microscopy and x-ray diffraction measurements demonstrate the occurrence of a complex reactivity at the Eu2O3/Si interface, leading to the formation of Eu2+ silicates, characterized by a very strong (the measured external quantum efficiency is about 10%) and broad room temperature photoluminescence (PL) peak centered at 590 nm. This signal is much more efficient than the Eu3+ emission, mainly consisting of a sharp PL peak at 622 nm, observed in O2-annealed films, where the presence of a SiO2 layer at the Eu2O3/Si interface prevents Eu2+ formation.noneGabriele, Bellocchi; Giorgia, FranzĂČ; Fabio, Iacona; Simona, Boninelli; Maria, Miritello; Cesca, Tiziana; Francesco, PrioloGabriele, Bellocchi; Giorgia, FranzĂČ; Fabio, Iacona; Simona, Boninelli; Maria, Miritello; Cesca, Tiziana; Francesco, Priol