7,294 research outputs found
Ranking Australian Economics Departments by Research Productivity
This study ranks Australian economics departments according to their average research productivity during 1998-2002. The highest ranked departments are those at ANU, JCU, Melbourne, Tasmania and UWA. We also rank departments according to the variability of research productivity among their members, the assumption being that, other things being equal, the less variable is productivity within a department, the better. Research productivity is found to be highly skewed within all departments. However, in general, research productivity is more (less) evenly distributed within those departments that have relatively high (low) average research productivity
Sensor architectures and technologies for upper limb 3d surface reconstruction: A review
3D digital models of the upper limb anatomy represent the starting point for the design process of bespoke devices, such as orthoses and prostheses, which can be modeled on the actual patient’s anatomy by using CAD (Computer Aided Design) tools. The ongoing research on optical scanning methodologies has allowed the development of technologies that allow the surface reconstruction of the upper limb anatomy through procedures characterized by minimum discomfort for the patient. However, the 3D optical scanning of upper limbs is a complex task that requires solving problematic aspects, such as the difficulty of keeping the hand in a stable position and the presence of artefacts due to involuntary movements. Scientific literature, indeed, investigated different approaches in this regard by either integrating commercial devices, to create customized sensor architectures, or by developing innovative 3D acquisition techniques. The present work is aimed at presenting an overview of the state of the art of optical technologies and sensor architectures for the surface acquisition of upper limb anatomies. The review analyzes the working principles at the basis of existing devices and proposes a categorization of the approaches based on handling, pre/post-processing effort, and potentialities in real-time scanning. An in-depth analysis of strengths and weaknesses of the approaches proposed by the research community is also provided to give valuable support in selecting the most appropriate solution for the specific application to be addressed
ALMA reveals the feeding of the Seyfert 1 nucleus in NGC 1566
We report ALMA observations of CO(3-2) emission in the Seyfert 1 galaxy NGC
1566, at a spatial resolution of 25 pc. Our aim is to investigate the
morphology and dynamics of the gas inside the central kpc, and to probe nuclear
fueling and feedback phenomena. NGC 1566 has a nuclear bar of 1.7 kpc radius
and a conspicuous grand design spiral starting from this radius. The ALMA field
of view, of diameter 0.9 kpc, lies well inside the nuclear bar and reveals a
molecular trailing spiral structure from 50 to 300~pc in size, which is
contributing to fuel the nucleus, according to its negative gravity torques.
The spiral starts with a large pitch angle from the center and then winds up
in a pseudo-ring at the inner Lindblad resonance (ILR) of the nuclear bar.
This is the first time that a trailing spiral structure is clearly seen
driving the gas inwards inside the ILR ring of the nuclear bar. This phenomenon
shows that the massive central black hole has a significant dynamical influence
on the gas, triggering its fueling.
The gaseous spiral is well correlated with the dusty spiral seen through
extinction in HST images, and also with a spiral feature emitting 0.87mm
continuum. This continuum emission must come essentially from cold dust heated
by the interstellar radiation field. The HCN(4-3) and HCO+(4-3) lines were
simultaneously mapped and detected in the nuclear spiral. The HCO+(4-3) line is
3 times stronger than the HCN(4-3), as expected when star formation excitation
dominates over active galactic nucleus (AGN) heating. The CO(3-2)/HCO+(4-3)
integrated intensity ratio is \sim 100.
The molecular gas is in remarkably regular rotation, with only slight
non-circular motions at the periphery of the nuclear spiral arms. These
perturbations are quite small, and no outflow nor AGN feedback is detected.Comment: 11 pages, 16 figures, accepted in Astronomy and Astrophysic
Mode of Delivery in Women with Stillbirth: Results of an Area-Based Italian Prospective Cohort Study
Introduction: The choice of the mode of delivery, in case of stillbirth (SB) (fetus non-viable >22 weeks' gestation), should consider maternal preference, gestational age, bishop score, the clinical condition of the woman, and her previous obstetric history. However, despite these clear indications, data on the effective implementation of the latter are lacking. The aim of our study is to evaluate the different modes of delivery in an Italian population of SBs, according to gestational age, parity, causes of death, obstetric history, and maternal characteristics. Material and Methods: This is an area-based, prospective cohort study conducted in Emilia Romagna, Italy between January 2014 to December 2020. Data included all cases of SB (>22 weeks). Results: From 2014 to 2020, 783 SB occurred out of a total of 232.506 births, with a SB rate of 3.3 per 1000. Labor was spontaneous in 85 (11%). Of remnant, 567 (73.6%) were induced and 118 (15.3%) had no labor. The mode of delivery was vaginal in most of the cases (649/770, 84.3%) and by cesarean section in 121/770 (15.7%) of cases. Emergency CS was most frequent and performed in 89/121 (73.5%) of total CS, representing 11.5% of SB deliveries. Mode of induction did not differ in relation to gestational age at stillbirth, while vaginal delivery was significantly higher in women induced with prostaglandins (p = 0.000) respect to other methods. Nulliparous women had a significantly higher need for multiple methods of induction (p = 0.000) respect multiparous and obese women used more frequently prostaglandins (p = 0.03) than other methods. Women with a history of previous CS presented a significantly higher rate of repeated elective CS (p = 0.000). Moreover, emergency CS was performed more frequent in obese (p = 0.02), diabetic (p = 0.04) and hypertensive (p = 0.04) women and in SB caused by placenta disorders, namely in abruptio placentae (p = 0.000). In the case of chorioamnionitis and funisitis women significantly were induced with prostaglandin (p = 0.000) and delivered vaginally (p = 0.000). Conclusions: The method of induction of labor and the mode of delivery in case of SB did not depend on gestational age at the diagnosis of death, while they are related to placenta disorders representing a relevant condition leading to emergency CS also after diagnosis of fetal death. These data could help obstetric providers in managing the deliveries of stillborn infants
Electromagnetic dipole moments of charged baryons with bent crystals at the LHC
We propose a unique program of measurements of electric and magnetic dipole
moments of charm, beauty and strange charged baryons at the LHC, based on the
phenomenon of spin precession of channeled particles in bent crystals. Studies
of crystal channeling and spin precession of positively- and negatively-charged
particles are presented, along with feasibility studies and expected
sensitivities for the proposed experiment using a layout based on the LHCb
detector.Comment: 19 pages, 13 figure
ALMA observations of feeding and feedback in nearby Seyfert galaxies: an AGN-driven outflow in NGC 1433
We report ALMA observations of CO(3-2) emission in the Seyfert 2
double-barred galaxy NGC1433, at the unprecedented spatial resolution of
0.5"=24 pc. Our aim is to probe AGN feeding and feedback phenomena through the
morphology and dynamics of the gas inside the central kpc. The CO map, which
covers the whole nuclear region (nuclear bar and ring), reveals a nuclear
gaseous spiral structure, inside the nuclear ring encircling the nuclear
stellar bar.
This gaseous spiral is well correlated with the dusty spiral seen in Hubble
Space Telescope images. The nuclear spiral winds up in a pseudo-ring at 200 pc
radius, which might correspond to the inner ILR. Continuum emission is detected
at 0.87 mm only at the very centre, and its origin is more likely thermal dust
emission than non-thermal emission from the AGN. It might correspond to the
molecular torus expected to exist in this Seyfert 2 galaxy. The HCN(4-3) and
HCO+(4-3) lines were observed simultaneously, but only upper limits are
derived, with a ratio to the CO(3-2) line lower than 1/60 at 3sigma, indicating
a relatively low abundance of very dense gas. The kinematics of the gas over
the nuclear disk reveal rather regular rotation only slightly perturbed by
streaming motions due to the spiral; the primary and secondary bars are too
closely aligned with the galaxy major or minor axis to leave a signature in the
projected velocities. Near the nucleus, there is an intense high-velocity CO
emission feature redshifted to 200 km/s (if located in the plane), with a
blue-shifted counterpart, at 2" (100 pc) from the centre. While the CO spectra
are quite narrow in the centre, this wide component is interpreted as an
outflow involving a molecular mass of 3.6 10^6 Mo and a flow rate 7 Mo/yr. The
flow could be in part driven by the central star formation, but is mainly
boosted by the AGN through its wind or radio jets.Comment: 11 pages, 9 figures, Accepted in Astronomy and Astrophysic
Spectra of sparse non-Hermitian random matrices: an analytical solution
We present the exact analytical expression for the spectrum of a sparse
non-Hermitian random matrix ensemble, generalizing two classical results in
random-matrix theory: this analytical expression forms a non-Hermitian version
of the Kesten-Mckay law as well as a sparse realization of Girko's elliptic
law. Our exact result opens new perspectives in the study of several physical
problems modelled on sparse random graphs. In this context, we show
analytically that the convergence rate of a transport process on a very sparse
graph depends upon the degree of symmetry of the edges in a non-monotonous way.Comment: 5 pages, 5 figures, 12 pages supplemental materia
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