64 research outputs found
CoRoT-TESS eclipsing binaries with light-travel-time effect
Identifying long-period eclipsing binaries with space-based photometry is
still a challenge even in the century of space telescopes due to the relatively
short observation sequences and short lifetime of these missions. The
Transiting Exoplanet Survey Satellite (TESS) space telescope is an appropriate
tool to supplement previous space-based observations. In this paper we report
the first results of the eclipse timing variation (ETV) analyses of eclipsing
binaries (EBs) measured by CoRoT and TESS space telescopes. Among the 1428 EB
candidates we found 4 new potential triple candidates, for which ETV was
analysed and fitted by the well-known light-travel-time effect (LTTE). One of
them shows significant phase shift in its folded light curve which required
extra care. In this paper we also present some other systems showing
significant ETV signals that could be explained by mass transfer or apsidal
motion.Comment: 6 pages, 5 figures, accepted for publication in MNRAS. Table 3 is
available as online supplementary materia
Geostrategy at the EU’s South-Eastern Gate
The study presents the geostrategic causes of Asian and African migration to Europe since 2015. Illustrated with maps and technical border protection data, it presents the Hungarian government’s response measures and its effects, with particular regard to the Southeastern border region of the European Union and the Schengen border region. The study highlights the geostrategic significance of the global process affecting Europe
Web-based Integrated Development Environment for Event-Driven Applications
Event-driven programming is a popular methodology for the development of resource-constrained embedded systems. While it is a natural abstraction for applications that interface with the physical world, the disadvantage is that the control flow of a program is hidden in the maze of event handlers and call-back functions. TinyOS is a representative event-driven operating system, designed for wireless sensor networks, featuring a component-based architecture that promotes code reuse. In this paper, we present a web-based model-driven graphical design environment for TinyOS that visualizes the component hierarchy of an application, and captures its eventbased scheduling mechanism. In contrast with existing visual environments, our representation explicitly captures the control flow of the application through events and commands, which makes it easier to understand the program logic than studying the source code. The design environment supports two-way code generation: mapping the visual representation to TinyOS source code, as well as building visual models from existing sources
A search for tight hierarchical triple systems amongst the eclipsing binaries in the CoRoT fields
We report a comprehensive search for hierarchical triple stellar system candidates amongst eclipsing binaries (EB) observed by the CoRoT spacecraft. We calculate and check eclipse timing variation (ETV) diagrams for almost 1500 EBs in an automated manner. We identify five relatively short-period Algol systems for which our combined light curve and complex ETV analyses (including both the light-travel time effect and short-term dynamical third-body perturbations) resulted in consistent third-body solutions. The computed periods of the outer bodies are between 82 and 272 days, (with an alternative solution of 831 days for one of the targets). We find that the inner and outer orbits are near coplanar in all but one case. The dynamical masses of the outer subsystems determined from the ETV analyses are consistent with both the results of our light curve analyses and the spectroscopic information available in the literature. One of our candidate systems exhibits outer eclipsing events as well, the locations of which are in good agreement with the ETV solution. We also report another certain triply eclipsing triple system which, however, is lacking a reliable ETV solution due to the very short time range of the data, and four new blended systems (composite light curves of 2 eclipsing binaries each), where we cannot decide whether the components are gravitationally binded or not. Amongst these blended systems we identify the longest period and highest eccentricity eclipsing binary in the entire CoRoT sample
Pathogenic variants in the DEAH-box RNA helicase DHX37 are a frequent cause of 46,XY gonadal dysgenesis and 46,XY testicular regression syndrome
PURPOSE: XY individuals with disorders/differences of sex development (DSD) are characterized by reduced androgenization caused, in some children, by gonadal dysgenesis or testis regression during fetal development. The genetic etiology for most patients with 46,XY gonadal dysgenesis and for all patients with testicular regression syndrome (TRS) is unknown. METHODS: We performed exome and/or Sanger sequencing in 145 individuals with 46,XY DSD of unknown etiology including gonadal dysgenesis and TRS. RESULTS: Thirteen children carried heterozygous missense pathogenic variants involving the RNA helicase DHX37, which is essential for ribosome biogenesis. Enrichment of rare/novel DHX37 missense variants in 46,XY DSD is highly significant compared with controls (P value = 5.8 × 10-10). Five variants are de novo (P value = 1.5 × 10-5). Twelve variants are clustered in two highly conserved functional domains and were specifically associated with gonadal dysgenesis and TRS. Consistent with a role in early testis development, DHX37 is expressed specifically in somatic cells of the developing human and mouse testis. CONCLUSION: DHX37 pathogenic variants are a new cause of an autosomal dominant form of 46,XY DSD, including gonadal dysgenesis and TRS, showing that these conditions are part of a clinical spectrum. This raises the possibility that some forms of DSD may be a ribosomopathy
The First Post-Kepler Brightness Dips of KIC 8462852
We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process
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