ABSTRACT
In the upcoming decades, large facilities, such as the SKA, will provide resolved observations of the kinematics of millions of galaxies. In order to assist in the timely exploitation of ...these vast data sets, we explore the use of a self-supervised, physics-aware neural network capable of Bayesian kinematic modelling of galaxies. We demonstrate the network’s ability to model the kinematics of cold gas in galaxies with an emphasis on recovering physical parameters and accompanying modelling errors. The model is able to recover rotation curves, inclinations and disc scale lengths for both CO and H i data which match well with those found in the literature. The model is also able to provide modelling errors over learned parameters, thanks to the application of quasi-Bayesian Monte Carlo dropout. This work shows the promising use of machine learning, and in particular, self-supervised neural networks, in the context of kinematically modelling galaxies. This work represents the first steps in applying such models for kinematic fitting and we propose that variants of our model would seem especially suitable for enabling emission-line science from upcoming surveys with e.g. the SKA, allowing fast exploitation of these large data sets.
Abstract
Next generation interferometers, such as the Square Kilometre Array, are set to obtain vast quantities of information about the kinematics of cold gas in galaxies. Given the volume of data ...produced by such facilities astronomers will need fast, reliable, tools to informatively filter and classify incoming data in real time. In this paper, we use machine learning techniques with a hydrodynamical simulation training set to predict the kinematic behaviour of cold gas in galaxies and test these models on both simulated and real interferometric data. Using the power of a convolutional autoencoder we embed kinematic features, unattainable by the human eye or standard tools, into a three-dimensional space and discriminate between disturbed and regularly rotating cold gas structures. Our simple binary classifier predicts the circularity of noiseless, simulated, galaxies with a recall of $85\%$ and performs as expected on observational CO and HI velocity maps, with a heuristic accuracy of $95\%$. The model output exhibits predictable behaviour when varying the level of noise added to the input data and we are able to explain the roles of all dimensions of our mapped space. Our models also allow fast predictions of input galaxies’ position angles with a 1σ uncertainty range of ±17○ to ±23○ (for galaxies with inclinations of 82.5○ to 32.5○, respectively), which may be useful for initial parameterisation in kinematic modelling samplers. Machine learning models, such as the one outlined in this paper, may be adapted for SKA science usage in the near future.
ABSTRACT There are few confirmed black holes with a mass of less and no neutron stars with masses greater than , creating a gap in the observed distribution of compact star masses. We present new ...optical photometry of the Low mass X-ray binary V1408 Aql, which is a persistent X-ray source thought to contain a black hole. The optical light curve of V1408 Aql shows nearly sinusoidal modulations at the orbital period, superimposed on large night-to-night variations. We combined this photometry with previously published photometry to derive a more precise orbital period of days. The orbital light curve agrees with a model in which the modulation is caused by the changing aspect of the heated face of the secondary. The lack of eclipses rules out orbital inclinations . Our best models favor inclinations near and black hole masses near with a 90% upper bound of , and a lower bound of imposed solely by the maximum mass of neutron stars. We favor a black hole primary over a neutron star based on evidence from the X-ray spectra, the high spin of the compact object, and the lack of any observed type I X-ray bursts. Although uncertainties in the data allow for higher masses, the compact star in V1408 Aql is a candidate for a black hole lying in the mass gap.
Pathology in Practice Anderson, Joseph A.; Stevens, Edward L.; Pierce, Virginia ...
Journal of the American Veterinary Medical Association,
07/2021, Letnik:
259, Številka:
2
Journal Article
La microtomografía computarizada es una herramienta importante para comprender la historia natural de las especies utilizando colecciones biológicas. Aquí reportamos los primeros datos de dieta de ...Alsodes cantillanensis Charrier, Correa, Castro & Méndez, 2015. Usando esta técnica, encontramos restos de Diplopoda y Coleóptera en el tracto digestivo de un macho de la localidad tipo, proporcionando valiosa información sobre la ecología de la especie. Estos hallazgos pueden ser útiles para diseñar estrategias de conservación para esta especie en peligro de extinción.
Abstract The Gemini High Resolution Optical Spectrograph (GHOST) is a fiber-fed spectrograph system on the Gemini South telescope that provides simultaneous wavelength coverage from 348 to 1061 nm, ...and is designed for optimal performance between 363 and 950 nm. It can observe up to two objects simultaneously in a 7.′5 diameter field of regard at R ≃ 56,000 or a single object at R ≃ 75,000. The spectral resolution modes are obtained by using integral field units to image slice a 1.″2 aperture by a factor of five in width using 19 fibers in the high resolution mode and by a factor of three in width using 7 fibers in the standard resolution mode. GHOST is equipped with hardware to allow for precision radial velocity measurements, expected to approach meters per second precision. Here, we describe the basic design and operational capabilities of GHOST, and proceed to derive and quantify the key aspects of its on-sky performance that are of most relevance to its science users.
Management and long-term outcome of neonatal Ebstein anomaly Shinkawa, Takeshi, MD; Polimenakos, Anastasios C., MD; Gomez-Fifer, Carlen A., MD ...
The Journal of thoracic and cardiovascular surgery,
02/2010, Letnik:
139, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Objective The objective of this study was to review the long-term results of symptomatic patients with Ebstein anomaly in the neonatal period. Methods The medical records of 40 neonates with a ...diagnosis of Ebstein anomaly who were admitted to our institution between January 1988 and June 2008 were retrospectively reviewed. Primary outcomes studied included patient survival and need for reintervention. Results No early intervention was required in 16 of the 40 patients with a hospital survival of 94% (15/16) and no late mortality. The remaining 24 patients underwent surgical intervention in the neonatal period. A shunt alone was performed in 9 patients with an actuarial survival of 88.9% at 1 year and 76.2% at 5 and 10 years. For the patients undergoing intervention on the tricuspid valve, survival estimates for the 11 patients with a right ventricular exclusion procedure were 63.6% at 1, 5, and 10 years and 47.7% at 15 years compared with 25.0% at 1, 5, and 10 years for the 4 patients with tricuspid valve repair. All long-term survivors were in New York Heart Association class I or II, and only 1 patient required antiarrhythmic medication. Conclusion Symptomatic neonates with Ebstein anomaly requiring no intervention or shunting alone have good long-term survival. For patients needing intervention on the tricuspid valve, overall survival is lower. For these patients, right ventricular exclusion may be superior to tricuspid valve repair.
The Meeting of the Electrochemistry Group of the Spanish Royal Society of Chemistry (RSEQ) is an annual event that has taken place since the late 1970s. The meeting brings together the entire Spanish ...electrochemistry community at a single event to discuss the latest advances in our field, and normally takes place in different Spanish cities. Over the last decade, mainly due to the deep economic crisis experienced in Spain, the number of electrochemists trained in Spain who have emigrated and today lead important groups in other European countries and in the USA has grown significantly. Thus, the XLI Meeting of the Electrochemistry Group was organized in Paris (France) in 2021, and served to regroup all electrochemists trained in Spain, both emigrants and residents. By holding the meeting outside of Spain, the Electrochemistry Group aimed to internationalize the group‘s meetings and to strengthen collaborations with the French electrochemistry community.
Stengthening collaborations with Spain: This Special Collection includes reports of the latest advances from expert researchers in environmental and energy applications within the growing field of electrochemistry. The articles provide important contributions towards the progress in France and Spain, and the international electrochemistry community, and the development of electrochemical solutions for the electrification of processes.
Currently, the survival for the Norwood procedure for hypoplastic left heart syndrome is approximately 90% in selected centers. However, the development of tricuspid regurgitation remains a ...significant obstacle to successful staged repair in a subset of these patients. The results of tricuspid valve repair in this challenging patient population remain largely unknown.
Twenty-eight patients with significant (3-4+) tricuspid regurgitation after the Norwood procedure required tricuspid valve repair from August 1995 through December 2002. The clinical and Doppler-echocardiographic data were reviewed to determine the efficacy of repair and patient outcome.
Follow-up was 96% complete (27/28). Patients were divided into 2 groups on the basis of tricuspid regurgitation at late follow-up: those with a successful late outcome (0-2+) and those with a poor outcome (3-4+). There were 17 (63%) patients with a successful result and 10 (37%) with an adverse outcome. Age, weight, follow-up duration, valve anatomy, and stage of palliation were not significantly different between groups. Early postoperative 0 to 2+ regurgitation was associated with a durable result (
P = .012) and preserved ventricular function (
P = .04). Need for repair other than a partial annuloplasty was predictive of a poor outcome (
P = .04). Overall survival was 67% (18/27). Survival was 94% (16/17) for patients with a successful late result versus 20% (2/10) for those with a poor outcome (
P = .0002).
Tricuspid valve repair can be accomplished in this challenging patient population with excellent results. Successful tricuspid valve repair is predictive of continued good valve function and preserved right ventricular function. Successful valve repair at late follow-up predicts excellent late survival.
On March 28– 29, 2017, the National Cancer Institute (NCI) Thoracic Malignacy Steering Committee, International Association for the Study of Lung Cancer, and Mesothelioma Applied Research Foundation ...convened the NCI–International Association for the Study of Lung Cancer– Mesothelioma Applied Research Foundation Mesothelioma Clinical Trials Planning Meeting in Bethesda, Maryland. The goal of the meeting was to bring together lead academicians, clinicians, scientists, and the U.S. Food and Drug Administration to focus on the development of clinical trials for patients in whom malignant pleural mesothelioma has been diagnosed. In light of the discovery of new cancer targets affecting the clinical development of novel agents and immunotherapies in malignant mesothelioma, the objective of this meeting was to assemble a consensus on at least two or three practice-changing multimodality clinical trials to be conducted through NCI’s National Clinical Trials Network.
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