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Publications

Publications by CTM

2022

Helping early obstructive sleep apnea diagnosis with machine learning: A systematic review (Preprint)

Authors
Ferreira-Santos, D; Amorim, P; Silva Martins, T; Monteiro-Soares, M; Pereira Rodrigues, P;

Publication

Abstract
BACKGROUND

American Academy of Sleep Medicine guidelines suggests that clinical prediction algorithms can be used to screen obstructive sleep apnea (OSA) patients without replacing polysomnography (PSG) – the gold standard.

OBJECTIVE

We aimed to identify, gather, and analyze existing machine learning approaches that are being used for disease screening in adult patients suspected of OSA.

METHODS

We searched MEDLINE, Scopus and ISI Web of Knowledge databases for evaluating the validity of different machine learning techniques, with PSG as the gold standard outcome measures. This systematic review was registered in PROSPERO under reference CRD42021221339.

RESULTS

Our search retrieved 5479 articles, of which 63 articles were included. We found 23 studies performing diagnostic models’ development alone, 26 with added internal validation, and 14 applying the clinical prediction algorithm to an independent sample (although not all reporting the most common discrimination metrics - sensitivity and/or specificity). Logistic regression was applied in 35 studies, linear regression in 16, support vector machine in 9, neural networks in 8, decision trees in 6, and Bayesian networks in 4. Random forest, discriminant analysis, classification and regression tree, and nomogram were each performed in 2 studies, while Pearson correlation, adaptative neuro-fuzzy inference system, artificial immune recognition system, genetic algorithm, supersparse linear integer models, and k-nearest neighbors’ algorithm each in 1 study. The best AUC was .98 [.96-.99] for age, waist circumference, Epworth somnolence, and oxygen saturation as predictors in a logistic regression.

CONCLUSIONS

Although high values were obtained, they still lack external validation results in large cohorts and a standard OSA criteria definition.

2022

Clinical Decision Support in the Care of Symptomatic Patients with COVID-19: An Approach Based on Machine Learning and Swarm Intelligence

Authors
Nunes, IB; de Lima, PVSG; Ribeiro, ALQ; Soares, LFF; da Silva Santana, ME; Barcelar, MLT; Gomes, JC; de Lima, CL; de Santana, MA; de Souza, RG; de Freitas Barbosa, VA; de Souza, RE; dos Santos, WP;

Publication
Swarm Intelligence Trends and Applications

Abstract

2022

Status Update on the Development of METIS, the Mid-Infrared ELT Imager and Spectrograph

Authors
Brandl, BR; Bettonvila, F; van Boekeld, R; Glauser, A; Quanz, SP; Absil, O; Feldt, M; Garcia, PJV; Glasse, A; Guedel, M; Labadie, L; Meyer, M; Pantin, E; Wang, SY; van Winckel, H; Agocs, T; Amorim, A; Bertram, T; Burtscher, L; Delacroix, C; Laun, W; Lesman, D; Raskin, G; Salo, C; Scheithauer, S; Stuik, R; Todd, S; Haupt, C; Siebenmorgen, R;

Publication
GROUND-BASED AND AIRBORNE INSTRUMENTATION FOR ASTRONOMY IX

Abstract
The Mid-Infrared ELT Imager and Spectrograph (METIS) is one of the first generation science instruments on ESO's 39m Extremely Large Telescope (ELT). METIS will provide diffraction-limited imaging and medium resolution slit-spectroscopy from 3 - 13 microns (L, M, and N bands), as well as high resolution (R similar to 100,000) integral field spectroscopy from 2.9 - 5.3 microns. Both imaging and IFU spectroscopy can be combined with coronagraphic techniques. After passing its preliminary design review (PDR) in May 2019, and the final design review (FDR) of its optical system in June 2021, METIS is now preparing for the FDR of its entire system in the fall of 2022, while the procurements of many optical components have already started. First light at the telescope is expected in 2028, after a comprehensive assembly integration and test phase. In this paper we focus mainly on the various design aspects, and present a status update on the final optical and mechanical design of METIS. We describe the conceptual setup of METIS, its key functional components, and the resulting observing modes. Last but not least, we present the expected scientific performance, in terms of sensitivity, adaptive optics, and high contrast imaging performance.

2022

Toward measuring supermassive black hole masses with interferometric observations of the dust continuum

Authors
Amorim, A; Bourdarot, G; Brandner, W; Cao, Y; Clénet, Y; Davies, R; De Zeeuw, PT; Dexter, J; Drescher, A; Eckart, A; Eisenhauer, F; Fabricius, M; Förster Schreiber, NM; Garcia, PJV; Genzel, R; Gillessen, S; Gratadour, D; Hönig, S; Kishimoto, M; Lacour, S; Lutz, D; Millour, F; Netzer, H; Ott, T; Paumard, T; Perraut, K; Perrin, G; Peterson, BM; Petrucci, PO; Pfuhl, O; Prieto, MA; Rouan, D; Santos, DJD; Shangguan, J; Shimizu, T; Sternberg, A; Straubmeier, C; Sturm, E; Tacconi, LJ; Tristram, KRW; Widmann, F; Woillez, J; GRAVITY, C;

Publication
ASTRONOMY & ASTROPHYSICS

Abstract
This work focuses on active galactic nuclei (AGNs) and on the relation between the sizes of the hot dust continuum and the broad-line region (BLR). We find that the continuum size measured using optical/near-infrared interferometry (OI) is roughly twice that measured by reverberation mapping (RM). Both OI and RM continuum sizes show a tight relation with the H beta BLR size, with only an intrinsic scatter of 0.25 dex. The masses of supermassive black holes (BHs) can hence simply be derived from a dust size in combination with a broad line width and virial factor. Since the primary uncertainty of these BH masses comes from the virial factor, the accuracy of the continuum-based BH masses is close to those based on the RM measurement of the broad emission line. Moreover, the necessary continuum measurements can be obtained on a much shorter timescale than those required monitoring for RM, and they are also more time efficient than those needed to resolve the BLR with OI. The primary goal of this work is to demonstrate a measuring of the BH mass based on the dust-continuum size with our first calibration of the R-BLR-R-d relation. The current limitation and caveats are discussed in detail. Future GRAVITY observations are expected to improve the continuum-based method and have the potential of measuring BH masses for a large sample of AGNs in the low-redshift Universe.

2022

First light for GRAVITY Wide Large separation fringe tracking for the Very Large Telescope Interferometer

Authors
Abuter, R; Allouche, F; Amorim, A; Bailet, C; Baubock, M; Berger, JP; Berio, P; Bigioli, A; Boebion, O; Bolzer, ML; Bonnet, H; Bourdarot, G; Bourget, P; Brandner, W; Clenet, Y; Courtney Barrer, B; Dallilar, Y; Davies, R; Defrere, D; Delboulbe, A; Delplancke, F; Dembet, R; de Zeeuw, PT; Drescher, A; Eckart, A; Edouard, C; Eisenhauer, F; Fabricius, M; Feuchtgruber, H; Finger, G; Schreiber, NMF; Garcia, E; Garcia, P; Gao, F; Gendron, E; Genzel, R; Gil, JP; Gillessen, S; Gomes, T; Gonte, F; Gouvret, C; Guajardo, P; Guieu, S; Hartl, M; Haubois, X; Haussmann, F; Heissel, G; Henning, T; Hippler, S; Honig, S; Horrobin, M; Hubin, N; Jacqmart, E; Jochum, L; Jocou, L; Kaufer, A; Kervella, P; Korhonen, H; Kreidberg, L; Lacour, S; Lagarde, S; Lai, O; Lapeyrere, V; Laugier, R; Le Bouquin, JB; Leftley, J; Lena, P; Lutz, D; Mang, F; Marcotto, A; Maurel, D; Merand, A; Millour, F; More, N; Nowacki, H; Nowak, M; Oberti, S; Ott, T; Pallanca, L; Paumard, T; Perraut, K; Perrin, G; Petrov, R; Pfuhl, O; Pourre, N; Rabien, S; Rau, C; Robbe Dubois, S; Rochat, S; Salman, M; Scholler, M; Schubert, J; Schuhler, N; Shangguan, J; Shimizu, T; Scheithauer, S; Sevin, A; Soulez, F; Spang, A; Stadler, E; Stadler, J; Straubmeier, C; Sturm, E; Tacconi, LJ; Tristram, KRW; Vincent, F; von Fellenberg, S; Uysal, S; Widmann, F; Wieprecht, E; Wiezorrek, E; Woillez, J; Yazici, S; Young, A; Zins, G;

Publication
ASTRONOMY & ASTROPHYSICS

Abstract
GRAVITY+ is the upgrade for GRAVITY and the Very Large Telescope Interferometer (VLTI) with wide-separation fringe tracking, new adaptive optics, and laser guide stars on all four 8 m Unit Telescopes (UTs) to enable ever-fainter, all-sky, high-contrast, milliarcsecond interferometry. Here we present the design and first results of the first phase of GRAVITY+, known as GRAVITY Wide. GRAVITY Wide combines the dual-beam capabilities of the VLTI and the GRAVITY instrument to increase the maximum separation between the science target and the reference star from 2 arcseconds with the 8 m UTs up to several 10 arcseconds, limited only by the Earth's turbulent atmosphere. This increases the sky-coverage of GRAVITY by two orders of magnitude, opening up milliarcsecond resolution observations of faint objects and, in particular, the extragalactic sky. The first observations in 2019-2022 include the first infrared interferometry of two redshift z similar to 2 quasars, interferometric imaging of the binary system HD 105913A, and repeat observations of multiple star systems in the Orion Trapezium Cluster. We find the coherence loss between the science object and fringe-tracking reference star well described by the turbulence of the Earth's atmosphere. We confirm that the larger apertures of the UTs result in higher visibilities for a given separation due to the broader overlap of the projected pupils on the sky and provide predictions for visibility loss as a function of separation to be used for future planning.

2022

Challenges to the assembly and integration of the WSS with METIS

Authors
Filho, M; Amorim, A; Garcia, P; Carvalho, F; da Costa, R; Ngando, M;

Publication
MODELING, SYSTEMS ENGINEERING, AND PROJECT MANAGEMENT FOR ASTRONOMY X

Abstract
Portugal will build the warm support and access structure (WSS) to the mid-infrared, first generation ELT instrument METIS. The particular characteristics of METIS and the ELT pose several challenges to designing the WSS according to requirements, as well challenges to the assembly and integration of the WSS. We here provide you an overview of those challenges, as well as strategies to overcome and mitigate issues related to the mass and dimensions of the WSS.

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