2024
Autores
Monteiro-Soares, M; Dores, J; Alves Palma, C; Galrito, S; Ferreira-Santos, D;
Publicação
Abstract
2024
Autores
de Lima P.V.S.G.; Gomes J.C.; Castro L.A.; Lins C.S.; Malheiro L.M.; Dos Santos W.P.;
Publicação
Biomedical Imaging: Principles and Advancements
Abstract
The advancement of the use of Artificial Intelligence (AI) in the healthcare sector makes it possible to use computational intelligence applications to assist healthcare professionals in the diagnosis process, facilitating and optimizing early detection and allowing for a more accurate diagnosis (He et al., 2019). The application of machine learning methods, and, more recently, deep learning, has shown promising results (Barbosa et al., 2022; da Silva et al., 2021; De Oliveira et al., 2020; Espinola et al., 2021a, b; Gomes et al., 2021, 2023; Santana et al., 2018; Torcate et al., 2022). These approaches allow powerful tools to support diagnostic imaging and signs to be built, through the extraction of image features and the creation of a classification system, for example (Yu et al., 2018). There are several diseases known and classified by man, with different causes and prevalence. Therefore, contributing to the early detection of diseases defined as neglected was the initial motivation for this work.
2024
Autores
Gomes, T; Correia, CM; Bardou, L; Cetre, S; Kolb, J; Kulcsár, C; Leroux, F; Morris, T; Morujao, N; Neichel, B; Beuzit, JL; Garcia, P;
Publicação
ASTRONOMY & ASTROPHYSICS
Abstract
Context. The amount of adaptive optics (AO) telemetry generated by visible/near-infrared ground-based observatories is ever greater, leading to a growing need for a standardised data exchange format to support performance analysis, AO research, and development activities that involve large-scale telemetry mining, processing, and curation. Aims. This paper introduces the Adaptive Optics Telemetry (AOT) data exchange format as a standard for sharing AO telemetry from visible/infrared ground-based observatories. AOT is based on the flexible image transport system (FITS) and aims to provide unambiguous and consistent data access across various systems and configurations, including natural and single- or multiple-laser guide-star AO systems. Methods. We designed AOT with a focus on two key use cases: atmospheric turbulence parameter estimation and point-spread function reconstruction. We prototyped and tested the design using existing AO telemetry datasets from multiple systems: single conjugate with natural and laser guide stars, tomographic systems with multi-channel wavefront sensors, and single- and multi-wavefront correctors in systems featuring either a Shack-Hartmann or Pyramid as the main wavefront sensor. Results. The AOT file structure has been thoroughly defined, with specified data fields, descriptions, data types, units, and expected dimensions. To support this format, we have developed a Python package that enables the data conversion, reading, writing, and exploration of AOT files; it has been made publicly available and is compatible with a general-purpose Python package manager. We have demonstrated the flexibility of the AOT format by packaging data from five different instruments, installed on different telescopes.
2024
Autores
Abuter, R; Allouche, F; Amorim, A; Bailet, C; Berdeu, A; Berger, JP; Berio, P; Bigioli, A; Boebion, O; Bolzer, ML; Bonnet, H; Bourdarot, G; Bourget, P; Brandner, W; Cao, Y; Conzelmann, R; Comin, M; Clénet, Y; Courtney-Barrer, B; Davies, R; Defrère, D; Delboulbsé, A; Delplancke-Ströbele, F; Dembet, R; Dexter, J; de Zeeuw, PT; Drescher, A; Eckart, A; Édouard, C; Eisenhauer, F; Fabricius, M; Feuchtgruber, H; Finger, G; Schreiber, NMF; Garcia, P; Lopez, RG; Gao, F; Gendron, E; Genzel, R; Gil, JP; Gillessen, S; Gomes, T; Gonté, F; Gouvret, C; Guajardo, P; Guieu, S; Hackenberg, W; Haddad, N; Hartl, M; Haubois, X; Haussmann, F; Heissel, G; Henning, T; Hippler, S; Hönig, SF; Horrobin, M; Hubin, N; Jacqmart, E; Jocou, L; Kaufer, A; Kervella, P; Kolb, J; Korhonen, H; Lacour, S; Lagarde, S; Lai, O; Lapeyrère, V; Laugier, R; Le Bouquin, JB; Leftley, J; Léna, P; Lewis, S; Liu, D; Lopez, B; Lutz, D; Magnard, Y; Mang, F; Marcotto, A; Maurel, D; Mérand, A; Millour, F; More, N; Netzer, H; Nowacki, H; Nowak, M; Oberti, S; Ott, T; Pallanca, L; Paumard, T; Perraut, K; Perrin, G; Petrov, R; Pfuhl, O; Pourré, N; Rabien, S; Rau, C; Riquelme, M; Robbe-Dubois, S; Rochat, S; Salman, M; Sanchez-Bermudez, J; Santos, DJD; Scheithauer, S; Schöller, M; Schubert, J; Schuhler, N; Shangguan, J; Shchekaturov, P; Shimizu, TT; Sevin, A; Soulez, F; Spang, A; Stadler, E; Sternberg, A; Straubmeier, C; Sturm, E; Sykes, C; Tacconi, LJ; Tristram, KRW; Vincent, F; von Fellenberg, S; Uysal, S; Widmann, F; Wieprecht, E; Wiezorrek, E; Woillez, J; Zins, G;
Publicação
NATURE
Abstract
Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-mu as (0.31-pc) spatial offset between the red and blue photocentres of the H alpha line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 x 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 x 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems. Using the GRAVITY+ instrument, dynamical measurement of the black hole mass in a quasar at a redshift of 2.3 (11 billion years ago) shows how the relationship between galaxies and black holes evolves with time.
2024
Autores
Amorim, A; Filho, M; Garcia, P; Carvalho, F; Lesman, D;
Publicação
GROUND-BASED AND AIRBORNE INSTRUMENTATION FOR ASTRONOMY X
Abstract
METIS is a first light mid-infrared instrument for the new ESO/ELT telescope. It includes a cryostat with a mass of more than ten tons that must face the telescope optical beam placed 6 m above the telescope Nasmyth instrument mounting platform. To overcome this height and allow the overall alignment of the field and pupil of the entrance beam, a large size structure has been designed, analyzed and optimized and is now being manufactured. To minimize the overall mass, the beam attachments do not fit in a vertical/horizontal grid but are oblique in a 3D structure. In building this structure one needs to combine 3D CNC machined parts of reasonable dimensions with several welded structural tube structures. Due to the sizes involved, these subsystems must be manufactured accurately within an angle tolerance of 0.1 degrees, imposing challenges on the welding process. The overall approaches to the main problems, together with the structures needed for the assembly, integration and transport. are discussed.
2024
Autores
Berdeu, A; Bonnet, H; Le Bouquin, JB; Edouard, C; Gomes, T; Shchekaturov, P; Dembet, R; Paumard, T; Oberti, S; Kolb, J; Millour, F; Berio, P; Lai, O; Eisenhauer, F; Garcia, P; Straubmeier, C; Kreidberg, L; Hoenig, SF; Defrere, D;
Publicação
ASTRONOMY & ASTROPHYSICS
Abstract
Context. The GRAVITY+ upgrade implies a complete renewal of its adaptive optics (AO) systems. Its complex design, featuring moving components between the deformable mirrors and the wavefront sensors, requires the monitoring and auto-calibrating of the lateral mis-registrations of the system while in operation. Aims. For preset and target acquisition, large lateral registration errors must be assessed in open loop to bring the system to a state where the AO loop closes. In closed loop, these errors must be monitored and corrected, without impacting the science. Methods. With respect to the first requirement, our method is perturbative, with two-dimensional modes intentionally applied to the system and correlated to a reference interaction matrix. For the second requirement, we applied a non-perturbative approach that searches for specific patterns in temporal correlations in the closed loop telemetry. This signal is produced by the noise propagation through the AO loop. Results. Our methods were validated through simulations and on the GRAVITY+ development bench. The first method robustly estimates the lateral mis-registrations, in a single fit and with a sub-subaperture resolution while in an open loop. The second method is not absolute, but it does successfully bring the system towards a negligible mis-registration error, with a limited turbulence bias. Both methods proved to robustly work on a system still under development and not fully characterised. Conclusions. Tested with Shack-Hartmann wavefront sensors, the proposed methods are versatile and easily adaptable to other AO instruments, such as the pyramid, which stands as a baseline for all future AO systems. The non-perturbative method, not relying on an interaction matrix model and being sparse in the Fourier domain, is particularly suitable to the next generation of AO systems for extremely large telescopes that will present an unprecedented level of complexity and numbers of actuators.
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