737 research outputs found
Variable star classification across the Galactic bulge and disc with the VISTA Variables in the Vía Láctea survey
We present VIVACE, the VIrac VAriable Classification Ensemble, a catalogue of variable stars extracted from an automated classification pipeline for the Vista Variables in the Vía Láctea (VVV) infrared survey of the Galactic bar/bulge and southern disc. Our procedure utilises a two-stage hierarchical classifier to first isolate likely variable sources using simple variability summary statistics and training sets of non-variable sources from the Gaia early third data release, and then classify candidate variables using more detailed light curve statistics and training labels primarily from OGLE and VSX. The methodology is applied to point-spread-function photometry for ∼490 million light curves from the VIRAC v2 astrometric and photometric catalogue resulting in a catalogue of ∼1.4 million likely variable stars, of which ∼39, 000 are high-confidence (classification probability >0.9) RR Lyrae ab stars, ∼8000 RR Lyrae c/d stars, ∼187, 000 detached/semi-detached eclipsing binaries, ∼18, 000 contact eclipsing binaries, ∼1400 classical Cepheid variables and ∼2200 Type II Cepheid variables. Comparison with OGLE-4 suggests a completeness of around 90 per cent for RRab and ≲ 60 per cent for RRc/d, and a misclassification rate for known RR Lyrae stars of around 1 per cent for the high confidence sample. We close with two science demonstrations of our new VIVACE catalogue: first, a brief investigation of the spatial and kinematic properties of the RR Lyrae stars within the disc/bulge, demonstrating the spatial elongation of bar-bulge RR Lyrae stars is in the same sense as the more metal-rich red giant population whilst having a slower rotation rate of ∼40 km s−1kpc−1; and secondly, an investigation of the Gaia EDR3 parallax zeropoint using contact eclipsing binaries across the Galactic disc plane and bulge
Graphical Reasoning in Compact Closed Categories for Quantum Computation
Compact closed categories provide a foundational formalism for a variety of
important domains, including quantum computation. These categories have a
natural visualisation as a form of graphs. We present a formalism for
equational reasoning about such graphs and develop this into a generic proof
system with a fixed logical kernel for equational reasoning about compact
closed categories. Automating this reasoning process is motivated by the slow
and error prone nature of manual graph manipulation. A salient feature of our
system is that it provides a formal and declarative account of derived results
that can include `ellipses'-style notation. We illustrate the framework by
instantiating it for a graphical language of quantum computation and show how
this can be used to perform symbolic computation.Comment: 21 pages, 9 figures. This is the journal version of the paper
published at AIS
HFE genotypes, haemochromatosis diagnosis and clinical outcomes at age 80 years: a prospective cohort study in the UK Biobank
This is the final version. Available on open access from BMJ Publishing Group via the DOI in this recordData availability statement Data may be obtained from a third party and are not publicly available. Data are available on application to the UK Biobank (www.ukbiobank.ac.uk/register-apply).OBJECTIVES: HFE haemochromatosis genetic variants have an uncertain clinical penetrance, especially to older ages and in undiagnosed groups. We estimated p.C282Y and p.H63D variant cumulative incidence of multiple clinical outcomes in a large community cohort. DESIGN: Prospective cohort study. SETTING: 22 assessment centres across England, Scotland, and Wales in the UK Biobank (2006-2010). PARTICIPANTS: 451 270 participants genetically similar to the 1000 Genomes European reference population, with a mean of 13.3-year follow-up through hospital inpatient, cancer registries and death certificate data. MAIN OUTCOME MEASURES: Cox proportional HRs of incident clinical outcomes and mortality in those with HFE p.C282Y/p.H63D mutations compared with those with no variants, stratified by sex and adjusted for age, assessment centre and genetic stratification. Cumulative incidences were estimated from age 40 years to 80 years. RESULTS: 12.1% of p.C282Y+/+ males had baseline (mean age 57 years) haemochromatosis diagnoses, with a cumulative incidence of 56.4% at age 80 years. 33.1% died vs 25.4% without HFE variants (HR 1.29, 95% CI: 1.12 to 1.48, p=4.7×10-4); 27.9% vs 17.1% had joint replacements, 20.3% vs 8.3% had liver disease, and there were excess delirium, dementia, and Parkinson's disease but not depression. Associations, including excess mortality, were similar in the group undiagnosed with haemochromatosis. 3.4% of women with p.C282Y+/+ had baseline haemochromatosis diagnoses, with a cumulative incidence of 40.5% at age 80 years. There were excess incident liver disease (8.9% vs 6.8%; HR 1.62, 95% CI: 1.27 to 2.05, p=7.8×10-5), joint replacements and delirium, with similar results in the undiagnosed. p.C282Y/p.H63D and p.H63D+/+ men or women had no statistically significant excess fatigue or depression at baseline and no excess incident outcomes. CONCLUSIONS: Male and female p.C282Y homozygotes experienced greater excess morbidity than previously documented, including those undiagnosed with haemochromatosis in the community. As haemochromatosis diagnosis rates were low at baseline despite treatment being considered effective, trials of screening to identify people with p.C282Y homozygosity early appear justified.National Institute for Health and Care Research (NIHR
VVV-WIT-04: An extragalactic variable source caught by the VVV Survey
We report the discovery of VVV-WIT-04, a near-infrared variable source
towards the Galactic disk located ~0.2 arcsec apart from the position of the
radio source PMN J1515-5559. The object was found serendipitously in the
near-IR data of the ESO public survey VISTA Variables in the V\'ia L\'actea
(VVV). Our analysis is based on variability, multicolor, and proper motion data
from VVV and VVV eXtended surveys, complemented with archive data at longer
wavelengths. We suggest that VVV-WIT-04 has an extragalactic origin as the
near-IR counterpart of PMN J1515-5559. The Ks-band light-curve of VVV-WIT-04 is
highly variable and consistent with that of an Optically Violent Variable (OVV)
quasar. The variability in the near-IR can be interpreted as the redshifted
optical variability. Residuals to the proper motion varies with the magnitude
suggesting contamination by a blended source. Alternative scenarios, including
a transient event such as a nova or supernova, or even a binary microlensing
event are not in agreement with the available data.R.K.S. acknowledges support from CNPq/Brazil through
projects 308968/2016-6 and 421687/2016-9. P.W.L. is supported by STFC Consolidated Grant ST/R000905/1. Support for the authors is provided by the BASAL CONICYT Center for Astrophysics and Associated Technologies
(CATA) through grant AFB-170002, and the Ministry for
the Economy, Development, and Tourism, Programa Iniciativa Cient´ıfica Milenio through grant IC120009, awarded to
the Millennium Institute of Astrophysics (MAS). D.M. acknowledges support from FONDECYT through project Regular #1170121
Evaluation of DSD training schools organized by cost action BM1303 "DSDnet"
Abstract Background The Differences of Sex Development network (DSDnet) aims to establish interactive relationships between clinicians, scientists, support groups and people with a difference of sex development (DSD) to improve the overall care for people affected by such condition. DSDnet has hosted three Training Schools (TSs) in Ghent, Bologna and Budapest between 2015 and 2017 with the primary purpose of providing multidisciplinary training to young professionals and encouraging ongoing activity in the field of DSD. The aim of our study was to evaluate the success and long-term effect effectiveness of these three TSs. Methods and results Eighty-seven trainees (70 women, 17 men) attended one of three TSs. The distribution of trainees according to their professional field was: 47 (54.0%) from Pediatrics/Endocrinology, 13 (14.9%) from Biology/Genetics, 12 (13.8%) from Psychology/Psychiatry and 15 (17.2%) from Surgical Professions. All trainees were asked to complete an evaluation form on the last day of the TS to gain feedback on how to improve the next one. A further survey was sent at the end of 2017 to provide information about the overall long-term impact of the TSs. Seventy-eight (89.7%) trainees completed evaluation forms at the end of the respective TSs. Replies to the subsequent survey were received from 76 (87.4%) of trainees. A total of 72/76 (94.7%) responders reported that they continue to be active in the field of DSD. The vast majority (64/68, 94.1%) reported that the TSs had enlarged their professional networks. Among the 76 respondent trainees, 11.8% (n = 9) had applied for a research grant and 10.5% (n = 8) had received a fellowship related to DSD since their TS attendance. Conclusions According to our results, the majority of TS participants continue to be active in the field of DSD and have enlarged their professional networks following participation at the TS. These findings indicate the need of this type of educational program and justify ongoing efforts to provide postgraduate multidisciplinary training in rare diseases such as DSD
Deciphering Network Community Structure by Surprise
The analysis of complex networks permeates all sciences, from biology to
sociology. A fundamental, unsolved problem is how to characterize the community
structure of a network. Here, using both standard and novel benchmarks, we show
that maximization of a simple global parameter, which we call Surprise (S),
leads to a very efficient characterization of the community structure of
complex synthetic networks. Particularly, S qualitatively outperforms the most
commonly used criterion to define communities, Newman and Girvan's modularity
(Q). Applying S maximization to real networks often provides natural,
well-supported partitions, but also sometimes counterintuitive solutions that
expose the limitations of our previous knowledge. These results indicate that
it is possible to define an effective global criterion for community structure
and open new routes for the understanding of complex networks.Comment: 7 pages, 5 figure
VVV-WIT-08: the giant star that blinked
We report the serendipitous discovery of a late-type giant star that exhibited a smooth, eclipse-like drop in flux to a depth of 97 per cent. Minimum flux occurred in 2012 April and the total event duration was a few hundred days. Light curves in V, I, and Ks from the Optical Gravitational Lensing Experiment and VISTA Variables in the Via Lactea surveys show a remarkably achromatic event. During 17 yr of observational coverage of this source only one such event was detected. The physical properties of the giant star itself appear somewhat unusual, which may ultimately provide a clue towards the nature of the system. By modelling the event as an occultation by an object that is elliptical in projection with uniform transparency, we place limits on its physical size and velocity. We find that the occultation is unlikely to be due to a chance alignment with a foreground object. We consider a number of possible candidates for the occulter, which must be optically thick and possess a radius or thickness in excess of 0.25 au. None are completely satisfactory matches to all the data. The duration, depth, and relative achromaticity of the dip mark this out as an exceptionally unusual event, whose secret has still not been fully revealed. We find two further candidates in the VVV survey and we suggest that these systems, and two previously known examples, may point to a broad class of long-period eclipsing binaries wherein a giant star is occulted by a circumsecondary disc
The effects of socioeconomic status and indices of physical environment on reduced birth weight and preterm births in Eastern Massachusetts
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Air pollution and social characteristics have been shown to affect indicators of health. While use of spatial methods to estimate exposure to air pollution has increased the power to detect effects, questions have been raised about potential for confounding by social factors.Methods: A study of singleton births in Eastern Massachusetts was conducted between 1996 and 2002 to examine the association between indicators of traffic, land use, individual and area-based socioeconomic measures (SEM), and birth outcomes ( birth weight, small for gestational age and preterm births), in a two-level hierarchical model.Results: We found effects of both individual ( education, race, prenatal care index) and area-based ( median household income) SEM with all birth outcomes. The associations for traffic and land use variables were mainly seen with birth weight, with an exception for an effect of cumulative traffic density on small for gestational age. Race/ethnicity of mother was an important predictor of birth outcomes and a strong confounder for both area-based SEM and indices of physical environment. The effects of traffic and land use differed by level of education and median household income.Conclusion: Overall, the findings of the study suggested greater likelihood of reduced birth weight and preterm births among the more socially disadvantaged, and a greater risk of reduced birth weight associated with traffic exposures. Results revealed the importance of controlling simultaneously for SEM and environmental exposures as the way to better understand determinants of health.This work is supported by the Harvard Environmental Protection Agency (EPA) Center,
Grants R827353 and R-832416, and National Institute for Environmental Health Science (NIEHS) ES-0002
Anaphylaxis to hyperallergenic functional foods
<p>Abstract</p> <p>Background</p> <p>Food allergy can cause life threatening reactions. Currently, patients with severe food allergy are advised to avoid foods which provoke allergic reactions. This has become increasingly difficult as food proteins are being added to a broader range of consumer products.</p> <p>Patients and methods</p> <p>Here we describe our investigations into the allergenicity of a new drink when two cow's milk allergic children suffered anaphylaxis after consuming <it>Wh</it><sub><it>2</it></sub><it>ole</it><sup>®</sup>.</p> <p>Results</p> <p>Our studies have shown that in comparison with cow's milk, <it>Wh</it><sub><it>2</it></sub><it>ole</it><sup>® </sup>contains at least three times the concentration of β-lactoglobulin. β-lactoglobulin is one of the dominant allergens in bovine milk.</p> <p>Conclusions</p> <p>These studies have shown that modern technology allows the creation of "hyperallergenic" foods. These products have the potential to cause severe reactions in milk allergic persons. Avoiding inadvertent exposure is the shared responsibility of allergic consumers, regulatory authorities and the food industry.</p
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