41 research outputs found
A Simplified ALE model for finite element simulation of ballistic impacts with bullet splash â development and experimental validation
An original simplified finite element model is proposed to simulate the effects of non-penetrating ballistic impacts causing the so-called bullet splash phenomenon (complete bullet fragmentation), while no fragmentation is caused to the target. The model is based on the Arbitrary Lagrangian Eulerian formulation (ALE) and it simulates the impact as a fluid-structure interaction. The bullet splash phenomenon has been tested by experimental analyses of AISI 304L plates impacted by 9x21 FMJ (full metal jacket) bullets. The model has been developed with the aim of creating a simplified approach to be used in the industry and forensic sciences to simulate the non-penetrating interaction of soft impactors with hard targets. Comparisons between evidence and simulation results lead to the conclusion that the proposed approach can be used in a conservative way to estimate both local and global effects of bullet-splash phenomena
Reliability and clinical usefulness of the personality inventory for DSM-5 in clinically referred adolescents. A preliminary report in a sample of Italian inpatients
Background The DSM-5 Alternative Model of Personality Disorders (AMPD) provides the opportunity to integrate the needed developmental perspective in the assessment of personality pathology. Based on this model, Krueger and colleagues (2012) developed the Personality Inventory for DSM-5 (PID-5), which operationalizes the proposed DSM-5 traits. Methods Eighty-five consecutively admitted Italian adolescent inpatients were administered the Italian translation of the PID-5, in order to obtain preliminary data on PID-5 reliability and clinical usefulness in clinically referred adolescents. Results With the possible exception of the PID-5 Suspiciousness scale, all other PID-5 scales evidenced adequate internal consistency reliability (i.e., Cronbach's α values of at least .70, most being greater than .80). Our data seemed to yield at least partial support for the construct validity of the PID-5 scales also in clinical adolescents, at least in terms of patterns of associations with dimensionally assessed DSM-5 Section II PDs that were also included in the DSM-5 AMPD (excluding Antisocial PD because of the participants' minor age). Finally, our data suggested that the clinical usefulness of the PID-5 in adolescent inpatients may extend beyond PDs to profiling adolescents at risk for life-threatening suicide attempts. In particular, PID-5 Depressivity, Anhedonia, and Submissiveness trait scales were significantly associated with adolescents' history of life-threatening suicide attempts, even after controlling for a number of other variables, including mood disorder diagnosis. Discussion As a whole, our study may provide interesting, albeit preliminary data as to the clinical usefulness of PID-5 in the assessment of adolescent inpatients
HST Observations of the Host Galaxies of BL Lacertae Objects
Six BL Lac objects from the complete 1 Jy radio-selected sample of 34 objects
were observed in Cycle 5 with the HST WFPC2 camera to an equivalent limiting
flux of mu_I~26 mag/arcsec^2. Here we report results for the second half of
this sample, as well as new results for the first three objects, discussed
previously by Falomo et al. (1997). In addition, we have analyzed in the same
way HST images of three X-ray-selected BL Lacs observed by Jannuzi et al.
(1997). The ensemble of 9 BL Lac objects spans the redshift range from z=0.19
to ~1. Host galaxies are clearly detected in seven cases, while the other two,
at z~0.258 (redshift highly uncertain) and z=0.997, are not resolved. The HST
images constitute a homogeneous data set with unprecedented morphological
information between a few tenths of an arcsecond and several arcseconds from
the nucleus, allowing us in 6 of the 7 detected host galaxies to rule out
definitively a pure disk light profile. The host galaxies are luminous
ellipticals with an average absolute magnitude of M_I~-24.6 mag (with
dispersion 0.7 mag), more than a magnitude brighter than L* and comparable to
brightest cluster galaxies. The morphologies are generally smooth and have
small ellipticities (epsilon<0.2). Given such roundness, there is no obvious
alignment with the more linear radio structures. In the six cases for which we
have HST WFPC2 images in two filters, the derived color profiles show no strong
spatial gradients and are as expected for K-corrected passively evolving
elliptical galaxies. The host galaxies of the radio-selected and X-ray-selected
BL Lacs for this very limited sample are comparable in both morphology and
luminosity.Comment: 23 pages, including 6 postscript figures and 3 tables (embedded).
Latex requires aaspp4.sty and psfig.sty (not included). Accepted for
publication in the Astrophysical Journa
The HST Survey of BL Lacertae Objects. II. Host Galaxies
We have used the HST WFPC2 camera to survey 132 BL Lac objects comprising
seven complete radio-, X-ray-, and optically-selected samples. We obtained
useful images for 110 targets spanning the redshift range 0 < z < 1.3. In two
thirds of the BL Lac images, host galaxies are detected, including nearly all
for z < 0.5 (58 of 63). The highest redshift host galaxy detected is in a BL
Lac object at z=0.664. In 58 of the 72 resolved host galaxies, a de Vaucouleurs
profile is significantly preferred, at >99% confidence, over a pure exponential
disk; the two fits are comparable in the remaining 14 cases. These results
limit the number of disk systems to at most 8% of BL Lacs (at 99% confidence),
and are consistent with all BL~Lac host galaxies being ellipticals. The
detected host galaxies are luminous ellipticals with a median absolute
K-corrected magnitude of M_R= -23.7 +- 0.6 mag, at least one magnitude brighter
than M* and comparable to brightest cluster galaxies. The galaxy morphologies
are generally smooth and undisturbed, with small or negligible ellipticities
(<0.2). There is no correlation between host galaxy and observed nuclear
magnitude or estimated jet power corrected for beaming. If black hole mass is
correlated linearly with bulge mass in general, this implies a large range in
Eddington ratio. Present data strongly support the unification picture with FR
I galaxies constituting the bulk of the parent population of BL Lac objects.Comment: Accepted for publication on ApJ. 38 pages, 8 figure
Technical and Functional Validation of a Teleoperated Multirobots Platform for Minimally Invasive Surgery
Nowadays Robotic assisted Minimally Invasive Surgeries (R-MIS) are the elective procedures for treating highly accurate and scarcely invasive pathologies, thanks to their abil- ity to empower surgeons\u2019 dexterity and skills. The research on new Multi-Robots Surgery (MRS) platform is cardinal to the development of a new SARAS surgical robotic platform, which aims at carrying out autonomously the assistants tasks during R- MIS procedures. In this work, we will present the SARAS MRS platform validation protocol, framed in order to assess: (i) its technical performances in purely dexterity exercises, and (ii) its functional performances. The results obtained show a prototype able to put the users in the condition of accomplishing the tasks requested (both dexterity- and surgical-related), even with rea- sonably lower performances respect to the industrial standard. The main aspects on which further improvements are needed result to be the stability of the end effectors, the depth per- ception and the vision systems, to be enriched with dedicated virtual fixtures. The SARAS\u2019 aim is to reduce the main surgeon\u2019s workload through the automation of assistive tasks which would benefit both surgeons and patients by facilitating the surgery and reducing the operation time
Five carbon- and nitrogen-bearing species in a hot giant planet's atmosphere
The atmospheres of gaseous giant exoplanets orbiting close to their parent
stars (hot Jupiters) have been probed for nearly two decades. They allow us to
investigate the chemical and physical properties of planetary atmospheres under
extreme irradiation conditions. Previous observations of hot Jupiters as they
transit in front of their host stars have revealed the frequent presence of
water vapour and carbon monoxide in their atmospheres; this has been studied in
terms of scaled solar composition under the usual assumption of chemical
equilibrium. Both molecules as well as hydrogen cyanide were found in the
atmosphere of HD 209458b, a well studied hot Jupiter (with equilibrium
temperature around 1,500 kelvin), whereas ammonia was tentatively detected
there and subsequently refuted. Here we report observations of HD 209458b that
indicate the presence of water (H2O), carbon monoxide (CO), hydrogen cyanide
(HCN), methane (CH4), ammonia (NH3) and acetylene (C2H2), with statistical
significance of 5.3 to 9.9 standard deviations per molecule. Atmospheric models
in radiative and chemical equilibrium that account for the detected species
indicate a carbon-rich chemistry with a carbon-to-oxygen ratio close to or
greater than 1, higher than the solar value (0.55). According to existing
models relating the atmospheric chemistry to planet formation and migration
scenarios, this would suggest that HD 209458b formed far from its present
location and subsequently migrated inwards. Other hot Jupiters may also show a
richer chemistry than has been previously found, which would bring into
question the frequently made assumption that they have solar-like and
oxygen-rich compositions.Comment: As part of the Springer Nature Content Sharing Initiative, it is
possible to access a view-only version of this paper by using the following
SharedIt link: https://rdcu.be/cifr
Enabling planetary science across light-years. Ariel Definition Study Report
Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution
Unpublished Mediterranean and Black Sea records of marine alien, cryptogenic, and neonative species
To enrich spatio-temporal information on the distribution of alien, cryptogenic, and
neonative species in the Mediterranean and the Black Sea, a collective effort by 173
marine scientists was made to provide unpublished records and make them open
access to the scientific community. Through this effort, we collected and harmonized
a dataset of 12,649 records. It includes 247 taxa, of which 217 are Animalia, 25 Plantae
and 5 Chromista, from 23 countries surrounding the Mediterranean and the Black
Sea. Chordata was the most abundant taxonomic group, followed by Arthropoda,
Mollusca, and Annelida. In terms of species records, Siganus luridus, Siganus rivulatus,
Saurida lessepsianus, Pterois miles, Upeneus moluccensis, Charybdis (Archias)
longicollis, and Caulerpa cylindracea were the most numerous. The temporal
distribution of the records ranges from 1973 to 2022, with 44% of the records in
2020â2021. Lethrinus borbonicus is reported for the first time in the Mediterranean
Sea, while Pomatoschistus quagga, Caulerpa cylindracea, Grateloupia turuturu,
and Misophria pallida are first records for the Black Sea; Kapraunia schneideri is
recorded for the second time in the Mediterranean and for the first time in Israel;
Prionospio depauperata and Pseudonereis anomala are reported for the first time
from the Sea of Marmara. Many first country records are also included, namely:
Amathia verticillata (Montenegro), Ampithoe valida (Italy), Antithamnion
amphigeneum (Greece), Clavelina oblonga (Tunisia and Slovenia), Dendostrea cf.
folium (Syria), Epinephelus fasciatus (Tunisia), Ganonema farinosum (Montenegro),
Macrorhynchia philippina (Tunisia), Marenzelleria neglecta (Romania), Paratapes
textilis (Tunisia), and Botrylloides diegensis (Tunisia).peer-reviewe
Trontano, localitĂ Causasca di Sotto. Possibili statue-stele dellâetĂ del Rame
Nel febbraio 2015 Riccardo Carazzetti, giĂ curatore del Museo Archeologico di Locarno e direttore dei servizi culturali
della cittĂ , notĂČ la statua-stele S.1 dal treno della Ferrovia Vigezzina-Centovalli. Successivamente fu in grado di identificare
e raggiungere a piedi il sito, segnalandolo alla Soprintendenza. Il 18 maggio 2019, dopo una lunga malattia, egli si Ăš spento allâetĂ
di 66 anni. Questo breve contributo si basa sul poster che presentĂČ al LII Convegno Scientifico dellâIstituto Italiano di Preistoria
e Protostoria. âPreistoria e Protostoria in Lombardia e Canton Ticinoâ (Milano-Como 17-21 ottobre 2017)
Possible statue-steles from the Copper Age in Causasca di Sotto, Trontano, Ossola Valley
In February 2015 Riccardo Carazzetti, former curator of the Archaeological Museum of Locarno and director of the cityâs
cultural services, saw the statue-stele S.1 from the train whilst travelling on the Vigezzina-Centovalli train line. Subsequently, he was
able to locate and reach the site, reporting it to the Superintendency. On May 18, 2019, after a long illness, he passed away at the age
of 66. This short contribution is based on a poster he presented at the LII Scientific Meeting of the Italian Institute of Prehistory and
Protohistory. âPrehistory and Protohistory in Lombardy and Canton Ticinoâ (Milan-Como 17-21 October 2017)