Search

With the advent of large-scale photometric surveys of the sky, modern science witnesses the dawn of big data astronomy, where automatic handling and discovery are paramount. In this context, classification tasks are among the key capabilities a data reduction pipeline must possess in order to compile reliable data sets, to accomplish data processing with an efficiency level impossible to achieve by means of detailed processing and human intervention. The VISTA Variables of the Vía Láctea Survey, in the southern part of the Galactic disc, comprises multiepoch photometric data necessary for the potential discovery of variable objects, including eclipsing binary systems (EBs). In this study, we use a recently published catalogue of one hundred EBs, classified by fine-tuning theoretical models according to contact, detached, or semidetached classes belonging to the tile d040 of the VVV. We describe the method implemented to obtain a supervised machine-learning model, capable of classifying EBs using information extracted from the light curves of variable object candidates in the phase space from tile d078. We also discuss the efficiency of the models, the relative importance of the features and the future prospects to construct an extensive data base of EBs in the VVV survey. [ABSTRACT FROM AUTHOR]

Most of our knowledge of the structure of the Milky Way has come from the study of variable stars. Among these variables, mimicking the periodic variation of pulsating stars, are eclipsing binaries. These stars are important in astrophysics because they allow us to directly measure the radii and masses of the components, as well as the distance to the system, thus being useful in studies of Galactic structure alongside pulsating RR Lyrae and Cepheids. Using the distinguishing features of their light curves, one can identify them using a semi-automated process. In this work, we present a strategy to search for eclipsing variables in the inner VVV bulge across an area of 13.4 deg2 within 1.68° < l < 7.53° and −3.73° < b < −1.44°, corresponding to the VVV tiles b293–b296 and b307–b310. We accurately classify 212 previously unknown eclipsing binaries, including six very reddened sources. A preliminary analysis suggests that these eclipsing binaries are located in the most obscured regions of the foreground disc and bulge of the Galaxy. This search is therefore complementary to other variable-star searches carried out at optical wavelengths. [ABSTRACT FROM AUTHOR]

We present Washington system colour-magnitude diagrams (CMDs) for 17 practically unstudied star clusters located in the bar as well as in the inner disc and outer regions of the Large Magellanic Cloud (LMC). Cluster sizes were estimated from star counts distributed throughout the entire observed fields. Based on the best fits of theoretical isochrones to the cleaned (C - T1, T1) CMDs, as well as on the δT1 parameter and the standard giant branch method, we derive ages and metallicities for the cluster sample. Four objects are found to be intermediate-age clusters (1.8-2.5 Gyr), with [Fe/H] ranging from -0.66 to -0.84. With the exception of SL 263, a very young cluster (~16 Myr), the remaining 12 objects are aged between 0.32 and 0.89 Gyr, with their [Fe/H] values ranging from -0.19 to -0.50. We combined our results with those for other 231 clusters studied in a similar way using the Washington system. The resulting age-metallicity relationship shows a significant dispersion in metallicities, whatever age is considered. Although there seems to exist a clear tendency for the younger clusters to be more metal rich than the intermediate ones, we believe that none of the chemical evolution models currently available in the literature reasonably well represents the recent chemical enrichment processes in the LMC clusters. The present sample of 17 clusters is part of our ongoing project of generating a data base of LMC clusters homogeneously studied using the Washington photometric system and applying the same analysis procedure. [ABSTRACT FROM AUTHOR]

Introduction: Brachial artery trauma is a rare but potentially devastating injury. There is little data regarding risk factors for reintervention and amputation prevention in this population, as well as anticoagulant (AC) and antiplatelet (AP) regimens and outcomes after discharge in trauma patients with vascular injuries requiring repair. This study aims to identify in-hospital risk factors for reintervention and amputation and stratify outcomes of follow-up by discharge AC or AP regimen., Methods: The AAST Prospective Observational Vascular Injury Trial database was queried for all patients who underwent traumatic brachial arterial repair from 2013 to 2022. Patients were evaluated by need for reintervention, amputation, and outcomes at follow-up by AC or AP regimen., Results: Three hundred and eleven patients required brachial repair, 28 (9%) required reoperation, and 8 (2.6%) required amputation. High injury severity score and an increased number of packed red blood cells and platelets showed a significant increase for reoperation and amputation. Damage control and shunt use were significant for the need to reoperate. Seventy-four percent (221/298) of patients were discharged with postoperative AC or AP regimens. There was no significant difference of short-term follow-up by type of AC or AP regimen., Conclusions: Damage control and temporary shunt may lead to additional operations but not an increase in amputations. However, anticoagulation intraoperatively and postoperatively does not appear to play a significant role in reducing reintervention. It also suggests that there is no increase in short-term follow-up complications with or without AC or AP therapy., (Published by Elsevier Inc.)

Mycobacterium bovis and Mycobacterium avium are the most important Mycobacteria isolated from diseased dogs, but Mycobacterium tuberculosis can be isolated as well, especially when close contact with humans exists. Free ranging street dogs may carry zoonotic diseases, being a potential health risk to new owners after adoption. In this study, the clinical case of a dog affected by Mycobacterium tuberculosis is described. A six-year-old bitch that had been living with a homeless man was rescued and put for adoption in dog shelter. After being adopted, her health declined, and abdominal ultrasound and exploratory laparoscopy were performed. A tuberculosis-like lesion in the liver was biopsied and histopathological, bacteriological, and molecular analyses were carried out. Then, the animal was euthanized and necropsied, and disseminated macroscopic tuberculosis-like lesions were observed in abdominal organs. Mycobacterium presence was confirmed by histopathological and bacteriological methods. Genotyping identified a SIT-1228 Mycobacterium tuberculosis strain. Notification to the sanitary authorities was performed and the couple that had contact with the dog were alerted and sent to the hospital for assessment, as Mycobacterium tuberculosis is a primary pathogenic agent for humans. The epidemiology in this clinical case is unclear, but the most likely source of infection might have been consumption of sputum contaminated food during the years that this bitch lived with the homeless man, because this person had died with chronic respiratory symptoms. Veterinarians must consider this disease and perform a complete diagnosis when dogs that used to live on the streets show nonspecific clinical signs., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

We report a case of acute rhegmatogenous retinal detachment (RRD) after laser in situ keratomileusis (LASIK) surgery in a highly myopic patient. Fourteen hours postoperatively, the uncorrected visual acuity was counting fingers in the left eye. Slitlamp examination revealed significant anterior chamber reaction with fibrin-like material. Fundus examination revealed 2 inferior retinal horseshoe tears associated with an RD. Preoperative fundus examination with scleral depression may detect predisposing retinal lesions in highly myopic patients. Further study is required to evaluate the relationship between LASIK, acute postoperative RRD, and predisposing factors.