1,289 research outputs found
New insular taxa from the oldest Terre Rosse fissure filling (Gargano, Southeastern Italy).
A rich amount of fossil remains of a highly diversified vertebrate fauna, known as “Mikrotia fauna”, has been retrieved from the red soil deposits (Terre Rosse) which fill the extensive palaeokarst network that affects the Mesozoic limestone along the north-western slopes of Mount Gargano (Southern Italy). The faunal assemblages reveal a rather complex history of bioevents such as dispersals and extinctions, which occurred when the area was isolated. These reconstructions were based on the materials collected during the seventies and the eighties of the last century.
Forty years after its discovery, the Gargano Terre Rosse finally yielded evidence of an older faunal settlement. The peculiar assemblage of the M013 fissure allows to explain some of the controversial aspects of the Gargano faunal history, namely, the matter of the biochronology of the older fissure fillings and the issue of the arrivals of the taxa in the insular domain. The taxonomic study of the small mammal assemblage from fissure M013, sampled by a team of the University of Torino during the 2005-09 excavations in the Dell’Erba Quarry (Apricena, Foggia), is here presented. Insectivores include a small-sized endemic Galericinae Apulogalerix cf. pusillus, together with a Crocidosoricinae, Lartetium cf. dehmi. Gliridae are well represented by the endemic species Stertomys simplex and S.lyrifer. Cricetids (l.s.) are represented by a single remain belonging to the endemic Hattomys cf. nazarii, but also by a new genus and species of an endemic and rather primitive Cricetodontinae. The latter shows a very hypsodont dental crown, stocky cusps and tubercle-like crests. Some of its features are typical of the continental genera of Cricetodontinae (i.e. large size, thick and crenulated enamel), however the very large size and the very high hypsodonty indicate the endemic nature of this taxon. The occlusal pattern appears rather primitive due to the very low, poorly developed, interrupted ectolophs and share some features with the primitive species of the genus Cricetodon. Murids include Mikrotia parva together with a second larger species, which is not yet identified. A third Murinae rodent is quite abundant, and belongs to a new genus and species. Its dentition is more brachyodont than in Mikrotia parva, the upper teeth are stephanodont and, accordingly, the transversal crests are joined by a longitudinal crest in the lower molars. Tubercle t7 is absent in the upper molars, t2bis is always present, while t1bis is usually absent in the first upper molar. Tubercle t1 is placed in a distal position respect to the t3, the posterolabial tubercle t12 is well-developed. Tubercles t3, t6 and t9 are roughly equidistant forming a regular pattern: a character that is found in Mikrotia and not in the other murid species, in which t6 is closer to t9. This morphological characters reveal a close relationship with Mikrotia, but they do not occur jointly in any of the Late Miocene-Earliest Pliocene European genera of murids, thus the phylogenetic origin of this new genus is still unclear. The occurrence of this new Murinae and of a Cricetodontinae distinguishes M013 from all the other Terre Rosse fissure fillings of Gargano. Stertomys lyrifer and S. simplex were previously known only from the very ancient fissure Rinascita 1. Because both taxa characterize M013 and Rinascita 1, the two fissures are believed to be very close chronologically. Also the Crocidosoricinae characterises the older fissure fillings. In contrast, M013 is the only fissure lacking Apodemus and Prolagus, which are otherwise present in all the other Gargano infillings.
The accumulated evidence indicates M013 as the oldest of Gargano’s faunal assemblages, despite the occurrence of Hattomys cf. nazarii, Mikrotia cf. parva and Mikrotia sp1, which most probably results from infiltrations from younger fissure fillings. The M013 assemblage is an absolute novelty for the Abruzzo-Apulian Palaeobioprovince and opens a new perspectives for the timing and mode of dispersal of the forerunners of the Gargano fauna
Data organization using gis for a more conscious conservation approach for abandoned sites
The purpose of this paper is to rediscover the abandoned village of Castelnuovo dei Sabbioni with new tools and modalities, providing an overall descriptive picture of the context in the framework of a pressing marginalization of territories subjected to depopulation and abandonment, and providing the appropriate tools for the definition of a possible future scenario for the village. The main novelty of this work is proposing alternative data recording and management strategies, preparatory to the definition of an actual project. The proposed strategy blends modern documentation technology and ICT processing tools with the consultation of more traditional sources of information, encouraging the adoption of a highly analytical structure in the design process. The paper, which brings a practical example, aims to support the implementation of interventions that are conscious, and targeted to the needs of future users and actors in the development of these places. Finally, the work aims at exploring the pros of offline and online GIS database in the case of historic sites through the development of shareable maps able to store multiple information
Perceptions of and Satisfaction with Sexual and Reproductive Health Interventions in Pre-Adolescent and Adolescent Students in UE/EEA Countries: A Systematic Review
: The objective of this review is to investigate perceptions of and satisfaction with sexual and reproductive health (SRH) interventions among pre-adolescents and adolescents of all genders and ethnicities in EU/EEA countries. This systematic review was conducted in accordance with PRISMA recommendations. A systematic literature search was conducted on MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (Central), CINAHL (EBSCO), and PsycINFO (EBSCO) up to March 2022 to identify all published articles that included information on perceptions and levels of satisfaction with SRH interventions. The selected studies were independently and blindly evaluated for risk of bias. Finally, only five papers were included in our review, divided according to the implemented intervention design: conducted by research groups (health or non-health professionals) or structured entirely in a peer-to-peer approach. Both types of program designs analyzed in the included studies were well accepted by students, even though satisfaction assessment methods were not standardized. Peer-to-peer conducted SRH programs or interventions with practical components (e.g., exercises, discussion) were more appreciated. We also found higher levels of satisfaction among younger participants. Future SRH educational programs should consider an assessment of participants' perceptions and satisfaction, possibly adopting standardized tools. Following a peer-to-peer structure and delivering programs early could lead to greater participant satisfaction
Water adsorption on amorphous silica surfaces: A Car-Parrinello simulation study
A combination of classical molecular dynamics (MD) and ab initio
Car-Parrinello molecular dynamics (CPMD) simulations is used to investigate the
adsorption of water on a free amorphous silica surface. From the classical MD
SiO_2 configurations with a free surface are generated which are then used as
starting configurations for the CPMD.We study the reaction of a water molecule
with a two-membered ring at the temperature T=300K. We show that the result of
this reaction is the formation of two silanol groups on the surface. The
activation energy of the reaction is estimated and it is shown that the
reaction is exothermic.Comment: 12 pages, 6 figures, to be published in J. Phys.: Condens. Matte
A growth-rate indicator for Compton-thick active galactic nuclei
Due to their heavily obscured central engines, the growth rate of
Compton-thick (CT) active galactic nuclei (AGN) is difficult to measure. A
statistically significant correlation between the Eddington ratio,
{\lambda}, and the X-ray power-law index, {\Gamma}, observed in
unobscured AGN offers an estimate of their growth rate from X-ray spectroscopy
(albeit with large scatter). However, since X-rays undergo reprocessing by
Compton scattering and photoelectric absorption when the line-of-sight to the
central engine is heavily obscured, the recovery of the intrinsic {\Gamma} is
challenging. Here we study a sample of local, predominantly Compton-thick
megamaser AGN, where the black hole mass, and thus Eddington luminosity, are
well known. We compile results on X-ray spectral fitting of these sources with
sensitive high-energy (E> 10 keV) NuSTAR data, where X-ray torus models which
take into account the reprocessing effects have been used to recover the
intrinsic {\Gamma} values and X-ray luminosities, L. With a simple
bolometric correction to L to calculate {\lambda}, we find a
statistically significant correlation between {\Gamma} and {\lambda} (p
= 0.007). A linear fit to the data yields {\Gamma} =
(0.410.18)log{\lambda}+(2.38 0.20), which is
statistically consistent with results for unobscured AGN. This result implies
that torus modeling successfully recovers the intrinsic AGN parameters. Since
the megamasers have low-mass black holes (M M)
and are highly inclined, our results extend the {\Gamma}-{\lambda}
relationship to lower masses and argue against strong orientation effects in
the corona, in support of AGN unification. Finally this result supports the use
of {\Gamma} as a growth-rate indicator for accreting black holes, even for
Compton-thick AGN.Comment: Accepted for publication in Ap
The NuSTAR Extragalactic Surveys: unveiling rare, buried AGNs and detecting the contributors to the peak of the Cosmic X-ray Background
We report on the results of active galactic nuclei (AGNs) detection by NuSTAR
performed in three extragalactic survey fields (COSMOS, UDS, ECDFS) in three
hard bands, namely H1 (8-16 keV), H2 (16-24 keV) and VH (35-55 keV). The
aggregated area of the surveys is deg. While a large number of
sources is detected in the H1 band (72 at the level of reliability), the
H2 band directly probing close to the peak of the Cosmic X-ray Background (CXB)
returns four significant detections, and two tentative, although not
significant, detections are found in the VH band. All the sources detected
above 16 keV are also detected at lower energies. We compute the integral
number counts for sources in such bands, which show broad consistency with
population synthesis models of the CXB. We furthermore identify two
Compton-thick AGNs, one in the COSMOS field, associated with a hard and faint
Chandra source, and one in the UDS field, never detected in the X-ray band
before. Both sources are at the same redshift , which shifts their
Compton-hump into the H1 band, and were previously missed in the usually
employed NuSTAR bands, confirming the potential of using the H1 band to
discover obscured AGNs at in deep surveys.Comment: 12 pages, 5 figures, accepted for publication in The Astrophysical
Journa
On the Design of Sidelink for Cellular V2X: A Literature Review and Outlook for Future
Connected and fully automated vehicles are expected to revolutionize our mobility in the near future on a global scale, by significantly improving road safety, traffic efficiency, and traveling experience. Enhanced vehicular applications, such as cooperative sensing and maneuvering or vehicle platooning, heavily rely on direct connectivity among vehicles, which is enabled by sidelink communications. In order to set the ground for the core contribution of this paper, we first analyze the main streams of the cellular-vehicle-to-everything (C-V2X) technology evolution within the Third Generation Partnership Project (3GPP), with focus on the sidelink air interface. Then, we provide a comprehensive survey of the related literature, which is classified and critically dissected, considering both the Long-Term Evolution-based solutions and the 5G New Radio-based latest advancements that promise substantial improvements in terms of latency and reliability. The wide literature review is used as a basis to finally identify further challenges and perspectives, which may shape the C-V2X sidelink developments in the next-generation vehicles beyond 5G
Georadar investigations to detect cavities in a historical town damaged by an earthquake of the past
This paper aims to highlight the use of the georadar as a useful prospecting
technique to identify the areal density and the geometrical features of the
grottoes placed in a historical town characterised by high seismic hazard.
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The town considered here is Rionero in Vulture (Southern Italy) that was hit
by several historical earthquakes, among which the 1930 Irpinia earthquake
(Me=6.7, Is=VIII MCS).
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For this event a damage map was already available from a previous study
(Gizzi and Masini, 2006). This map shows that some sectors of the town
suffered higher damage. One factor causing the uneven distribution of the
effects is considered to be the presence of grottoes.
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To strengthen this work hypothesis it was necessary to in-depth investigate
the subsoil of Rionero in Vulture. Therefore, geophysical data were
correlated and integrated with data obtained from field surveys and
historical documentary sources. All these investigations allowed to obtain
more insights about the influences of the man-made caves on seismic damage
Measuring the Obscuring Column of a Disk Megamaser AGN in a Nearby Merger
Active galactic nuclei (AGNs) hosting disk water megamasers are well known to be obscured by large amounts of gas, likely due to the presence along the line of sight of an almost edge-on disky structure orbiting the supermassive black hole. Correcting for the high obscuration is crucial to infer parameters intrinsic to the source, like its luminosity. We present a broadband X-ray spectral analysis of a water megamaser AGN in an early merger (NGC 5765B), combining Chandra and NuSTAR data. NGC 5765B is highly Compton-thick and reflection-dominated, following the general trend among disk megamasers. Combining the exquisite black hole mass from masers with our X-ray spectroscopy, the Eddington ratio of the megamaser is estimated to be in the 2%–14% range, and its robustness is confirmed through SED fitting
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