108,104 research outputs found
\u3ci\u3eAlfabeto Falso\u3c/i\u3e (Vallerotondo, I Bassifondi)
A review of Alfabeto falso, with Simone Vallerotondo (Baroque guitar) and I Bassifondi (Arcana A435, 2017), compact disc
DVD Review: Rossi, Luigi. L’Orfeo. Pygmalion, musical direction by Raphaël Pichon, staging by Jetske Mijnssen. Recorded at L’Opéra National de Lorraine (Nancy), February 7 and 9, 2016. Arles: Harmonia Mundi, 2017. HMD 9859058.59 DVD and Blu-ray Disc.
DVD Review: Rossi, Luigi. L’Orfeo. Pygmalion, musical direction by Raphaël Pichon, staging by Jetske Mijnssen. Recorded at L’Opéra National de Lorraine (Nancy), February 7 and 9, 2016. Arles: Harmonia Mundi, 2017. HMD 9859058.59 DVD and Blu-ray Disc.
Roger Freitas discusses a production of Rossi\u27s L\u27Orfeo recorded on DVD
Similarity regularized sparse group lasso for cup to disc ratio computation
© 2017 Optical Society of America. Automatic cup to disc ratio (CDR) computation from color fundus images has shown to be promising for glaucoma detection. Over the past decade, many algorithms have been proposed. In this paper, we first review the recent work in the area and then present a novel similarity-regularized sparse group lasso method for automated CDR estimation. The proposed method reconstructs the testing disc image based on a set of reference disc images by integrating the similarity between testing and the reference disc images with the sparse group lasso constraints. The reconstruction coefficients are then used to estimate the CDR of the testing image. The proposed method has been validated using 650 images with manually annotated CDRs. Experimental results show an average CDR error of 0.0616 and a correlation coefficient of 0.7, outperforming other methods. The areas under curve in the diagnostic test reach 0.843 and 0.837 when manual and automatically segmented discs are used respectively, better than other methods as well
Clinical application of ceramics in anterior cervical discectomy and fusion: A review and update
Study Design: Narrative review. Objectives: Anterior cervical discectomy and fusion (ACDF) is a reliable procedure, commonly used for cervical degenerative disc disease. For interbody fusions, autograft was the gold standard for decades; however, limited availability and donor site morbidities have led to a constant search for new materials. Clinically, it has been shown that calcium phosphate ceramics, including hydroxyapatite (HA) and tricalcium phosphate (TCP), are effective as osteoconductive materials and bone grafts. In this review, we present the current findings regarding the use of ceramics in ACDF. Methods: A review of the relevant literature examining the clinical use of ceramics in anterior cervical discectomy and fusion procedures was conducted using PubMed, OVID and Cochrane. Result: HA, coralline HA, sandwiched HA, TCP, and biphasic calcium phosphate ceramics were used in combination with osteoinductive materials such as bone marrow aspirate and various cages composed of poly-ether-ether-ketone (PEEK), fiber carbon, and titanium. Stand-alone ceramic spacers have been associated with fracture and cracks. Metallic cages such as titanium endure the risk of subsidence and migration. PEEK cages in combination with ceramics were shown to be a suitable substitute for autograft. Conclusion: None of the discussed options has demonstrated clear superiority over others, although direct comparisons are often difficult due to discrepancies in data collection and study methodologies. Future randomized clinical trials are warranted before definitive conclusions can be drawn. © The Author(s) 2017
Accretion and outflow structures within 1000 AU from high-mass protostars with ALMA longest baselines
Understanding the formation of massive stars is one of the unsolved problems
in modern astronomy. The main difficulty is that the intense radiation from the
high-luminosity stars and the thermal pressure from the resulting ionized gas
(both insignificant for low-mass stars) may be able to reverse the accretion
flow and prevent the star from accreting fresh material. Such feedback effects
can naturally be mitigated if accretion proceeds through discs, which is the
established mechanism to form sun-like stars. However, recent 3D MHD
simulations have shown that accretion on 1000 au scales is through filaments
rather than a large disc. This theoretical prediction has never been confirmed
via observations owing to the poor linear resolution of previous studies (>1000
au). Here we present the first observational evidence that mass assembly in
young high-mass stars forming in protoclusters is predominantly asymmetric and
disordered. In particular, we observed the innermost regions around three
deeply embedded high-mass protostars with very high spatial resolution (~100
au). We identified multiple massive (several solar masses), warm (50-150
Kelvin) filamentary streamers pointing onto the central sources, which we
interpret as multi-directional accretion channels. These structures inhibit the
formation of a large, steady disc. Nevertheless, the identification of fast
collimated outflows in the three observed systems indicates that (non-steady)
compact discs may be present (we measure upper limits on their radii of <80 for
one object and <350 astronomical units for the remaining two objects). Our
finding contrasts with the simplified classic paradigm of an ordered (and
stable) disc/jet system and provides an experimental confirmation of a
multi-directional and unsteady accretion model for massive star formation
supported by recent 3D (magneto)hydrodynamic simulations.Comment: Submitted to Nature on Dec 19 2017, transferred to Nature Astronomy
after review on February 8 2018, rejected after a recommendation for
acceptance by one reviewer, and a more critical report by a second reviewer.
To be submitted to ApJ. Comments from colleagues (even critical ones) are
welcom
The impact of baryonic discs on the shapes and profiles of self-interacting dark matter halos
We employ isolated N-body simulations to study the response of
self-interacting dark matter (SIDM) halos in the presence of the baryonic
potentials. Dark matter self-interactions lead to kinematic thermalization in
the inner halo, resulting in a tight correlation between the dark matter and
baryon distributions. A deep baryonic potential shortens the phase of SIDM core
expansion and triggers core contraction. This effect can be further enhanced by
a large self-scattering cross section. We find the final SIDM density profile
is sensitive to the baryonic concentration and the strength of dark matter
self-interactions. Assuming a spherical initial halo, we also study evolution
of the SIDM halo shape together with the density profile. The halo shape at
later epochs deviates from spherical symmetry due to the influence of the
non-spherical disc potential, and its significance depends on the baryonic
contribution to the total gravitational potential, relative to the dark matter
one. In addition, we construct a multi-component model for the Milky Way,
including an SIDM halo, a stellar disc and a bulge, and show it is consistent
with observations from stellar kinematics and streams.Comment: 10 pages, 8 figures, submitted to MNRAS, accepted for publication in
MNRA
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