The objective of this paper is to present a new type of volumetric CT which uses the cone-beam technique instead of traditional fan-beam technique. The machine is dedicated to the ...dento-maxillo-facial imaging, particularly for planning in the field of implantology. The main characteristics of the unit are presented with reference to the technical parameters as well as the software performance. Images obtained are reported as various 2D sections of a volume reconstruction. Also, measurements of the geometric accuracy and the radiation dose absorbed by the patient are obtained using specific phantoms. Absorbed dose is compared with that given off by spiral CT. Geometric accuracy, evaluated with reference to various reconstruction modalities and different spatial orientations, is 0.8-1% for width measurements and 2.2% for height measurements. Radiation dose absorbed during the scan shows different profiles in central and peripheral axes. As regards the maximum value of the central profile, dose from the new unit is approximately one sixth that of traditional spiral CT. The new system appears to be very promising in dentomaxillo-facial imaging and, due to the good ratio between performance and low cost, together with low radiation dose, very interesting in view of large-scale use of the CT technique in such diagnostic applications.
The Southern Apennines range of Italy presents significant challenges for active fault detection due to the complex structural setting inherited from previous contractional tectonics, coupled to very ...recent (Middle Pleistocene) onset and slow slip rates of active normal faults. As shown by the Irpinia Fault, source of a M6.9 earthquake in 1980, major faults might have small cumulative deformation and subtle geomorphic expression. A multidisciplinary study including morphological‐tectonic, paleoseismological, and geophysical investigations has been carried out across the extensional Monte Aquila Fault, a poorly known structure that, similarly to the Irpinia Fault, runs across a ridge and is weakly expressed at the surface by small scarps/warps. The joint application of shallow reflection profiling, seismic and electrical resistivity tomography, and physical logging of cored sediments has proved crucial for proper fault detection because performance of each technique was markedly different and very dependent on local geologic conditions. Geophysical data clearly (1) image a fault zone beneath suspected warps, (2) constrain the cumulative vertical slip to only 25–30 m, (3) delineate colluvial packages suggesting coseismic surface faulting episodes. Paleoseismological investigations document at least three deformation events during the very Late Pleistocene (<20 ka) and Holocene. The clue to surface‐rupturing episodes, together with the fault dimension inferred by geological mapping and microseismicity distribution, suggest a seismogenic potential of M6.3. Our study provides the second documentation of a major active fault in southern Italy that, as the Irpinia Fault, does not bound a large intermontane basin, but it is nested within the mountain range, weakly modifying the landscape. This demonstrates that standard geomorphological approaches are insufficient to define a proper framework of active faults in this region. More in general, our applications have wide methodological implications for shallow imaging in complex terrains because they clearly illustrate the benefits of combining electrical resistivity and seismic techniques. The proposed multidisciplinary methodology can be effective in regions characterized by young and/or slow slipping active faults.
We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the gas kinematics of the inner ∼200 × 500 pc2 of the Seyfert galaxy NGC 4151 in the Z, J, H and K bands at a resolving ...power of ≥5000 and spatial resolution of ∼8 pc. The ionized gas emission is most extended along the known ionization bi-cone at position angle PA = 60°–240°, but is observed also along its equatorial plane. This indicates that the active galactic nucleus (AGN) ionizes gas beyond the borders of the bi-cone, within a sphere with ≈1 arcsec radius around the nucleus. The ionized gas has three kinematic components: (1) one observed at the systemic velocity and interpreted as originating in the galactic disc; (2) one outflowing along the bi-cone, with line-of-sight velocities between −600 and 600 km s−1 and strongest emission at ±(100–300) km s−1; and (3) another component due to the interaction of the radio jet with ambient gas. The radio jet (at PA = 75°–255°) is not aligned with the narrow-line region (NLR) and produces flux enhancements mostly observed at the systemic velocity, suggesting that the jet is launched close to the plane of the galaxy (approximately plane of the sky). The mass outflow rate, estimated to be ≈1 M⊙ yr−1 along each cone, exceeds the inferred black hole accretion rate by a factor of ∼100. This can be understood if the NLR is formed mostly by entrained gas from the circumnuclear interstellar medium by an outflow probably originating in the accretion disc. This flow represents feedback from the AGN, estimated to release a kinetic power of , which is only ∼0.3 per cent of the bolometric luminosity of the AGN. There is no evidence in our data for the gradual acceleration followed by gradual deceleration proposed by previous modelling of the O iii emitting gas. Our data allow the possibility that the NLR clouds are accelerated close to the nucleus (within 0.1 arcsec, which corresponds to ≈7 pc at the galaxy) after which the flow moves at essentially constant velocity (≈600 km s−1), being consistent with near-infrared emission arising predominantly from the interaction of the outflow with gas in the galactic disc. The molecular gas exhibits distinct kinematics relative to the ionized gas. Its emission arises in extended regions approximately perpendicular to the axis of the bi-cone and along the axis of the galaxy's stellar bar, avoiding the innermost ionized regions. It does not show an outflowing component, being observed only at velocities very close to systemic, and is thus consistent with an origin in the galactic plane. This hot molecular gas may only be the tracer of a larger reservoir of colder gas which represents the AGN feeding.
The majority of patients with stage III–IV epithelial ovarian cancer (EOC) relapse after initially responding to platinum-based chemotherapy, and develop resistance. The genomic features involved in ...drug resistance are unknown. To unravel some of these features, we investigated the mutational profile of genes involved in pathways related to drug sensitivity in a cohort of matched tumors obtained at first surgery (Ft-S) and second surgery (Sd-S).
Matched biopsies (33) taken at Ft-S and Sd-S were selected from the ‘Pandora’ tumor tissue collection. DNA libraries for 65 genes were generated using the TruSeq Custom Amplicon kit and sequenced on MiSeq (Illumina). Data were analyzed using a high-performance cluster computing platform (Cloud4CARE project) and independently validated.
A total of 2270 somatic mutations were identified (89.85% base substitutions 8.19% indels, and 1.92% unknown). Homologous recombination (HR) genes and TP53 were mutated in the majority of Ft-S, while ATM, ATR, TOP2A and TOP2B were mutated in the entire dataset. Only 2% of mutations were conserved between matched Ft-S and Sd-S. Mutations detected at second surgery clustered patients in two groups characterized by different mutational profiles in genes associated with HR, PI3K, miRNA biogenesis and signal transduction.
There was a low level of concordance between Ft-S and Sd-S in terms of mutations in genes involved in key processes of tumor growth and drug resistance. This result suggests the importance of future longitudinal analyses to improve the clinical management of relapsed EOC.
We present the first results of a survey for high-redshift, z ≥ 6, quasars using izY multicolour photometric observations from the Dark Energy Survey (DES). Here we report the discovery and ...spectroscopic confirmation of the z
AB, Y
AB = 20.2, 20.2 (M
1450 = −26.5) quasar DES J0454−4448 with a redshift of z = 6.09±0.02 based on the onset of the Ly α forest and an H i near zone size of 4.1
$_{-1.2}^{+1.1}$
proper Mpc. The quasar was selected as an i-band drop out with i−z = 2.46 and z
AB < 21.5 from an area of ∼300 deg2. It is the brightest of our 43 candidates and was identified for spectroscopic follow-up solely based on the DES i−z and z−Y colours. The quasar is detected by WISE and has W1AB = 19.68. The discovery of one spectroscopically confirmed quasar with 5.7 < z < 6.5 and z
AB ≤ 20.2 is consistent with recent determinations of the luminosity function at z ∼ 6. DES when completed will have imaged ∼5000 deg2 to Y
AB = 23.0 (5σ point source) and we expect to discover 50–100 new quasars with z > 6 including 3–10 with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.
At Mt. Etna (Italy), volcano‐tectonic earthquakes produce impressive surface faulting despite their moderate magnitude (M < 5.5), with historically well‐documented ruptures featuring end‐to‐end ...lengths up to 6–7 km. The 26 December 2018, Mw 5.0 earthquake represents the strongest event of the last 70 years, with ground ruptures extending for 7.5 km along the Fiandaca fault, a partially hidden structure in the volcano's eastern flank. Field data collected by the EMERGEO Working Group (INGV) are here integrated with high‐resolution photogrammetric surveys and geological‐morphological observations to enable a detailed structural analysis and to reconstruct the morphotectonic process of fault growth. The deformation zone develops in a transtensional regime and shows a complex pattern, consisting of brittle structures arranged in en‐échelon scale‐invariant overlapping systems. Offsets and kinematics vary along the strike due to a major bend in the fault trace. We reconstructed a prevailing right‐lateral displacement in the northern section of the fault and a dextral oblique slip in the southern one (max 35 cm); the dip‐slip component increases southward (max 50 cm) and overall resembles the along‐strike pattern of the long‐term morphological throw. The kinematic analysis indicates a quasi‐rigid behavior of the two fault blocks and suggests a geological model of rupture propagation that explains both the location of the seismic asperity in the northern section of the Fiandaca fault and the unclamping in the southern one. These findings are used to propose a conceptual model of the fault, representing insights for local fault‐based seismic hazard assessment.
Key Points
The pattern of the 2018 rupture is characterized by scale‐invariant overlapping systems of structures organized in a hierarchical way
The along‐strike distribution of the coseismic vertical displacement mimics the pattern of the long‐term morphological throw of the fault
Findings constrain fault behavior and maximum expected magnitude as possible inputs for local fault‐based seismic hazard assessment
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