RESUMEN
Type Ia supernovae (SNe Ia) are thermonuclear explosions of degenerate white dwarf stars destabilized by mass accretion from a companion star1, but the nature of their progenitors remains poorly understood. A way to discriminate between progenitor systems is through radio observations; a non-degenerate companion star is expected to lose material through winds2 or binary interaction3 before explosion, and the supernova ejecta crashing into this nearby circumstellar material should result in radio synchrotron emission. However, despite extensive efforts, no type Ia supernova (SN Ia) has ever been detected at radio wavelengths, which suggests a clean environment and a companion star that is itself a degenerate white dwarf star4,5. Here we report on the study of SN 2020eyj, a SN Ia showing helium-rich circumstellar material, as demonstrated by its spectral features, infrared emission and, for the first time in a SN Ia to our knowledge, a radio counterpart. On the basis of our modelling, we conclude that the circumstellar material probably originates from a single-degenerate binary system in which a white dwarf accretes material from a helium donor star, an often proposed formation channel for SNe Ia (refs. 6,7). We describe how comprehensive radio follow-up of SN 2020eyj-like SNe Ia can improve the constraints on their progenitor systems.
RESUMEN
Skin infections are an important issue among participants in expedition-length adventure races. Prolonged stress, scant sleep, and water exposure mean that competitors are at risk of uncommon manifestations of infections. Ulcerative tinea pedis is an example of this. We present a case with characteristic clinical manifestations, including the "sandpaper symptom." There is limited literature exploring infectious foot complaints in expedition adventure racers. Beyond this case report, more research is needed to better understand incidence rates, risk factors, diagnostic measures, treatment, and prevention options.
Asunto(s)
Úlcera Cutánea/etiología , Úlcera Cutánea/patología , Deportes , Tiña del Pie/complicaciones , Tiña del Pie/patología , Adulto , Expediciones , Humanos , Masculino , Úlcera Cutánea/tratamiento farmacológico , Tiña del Pie/tratamiento farmacológicoRESUMEN
Fentanyl is a potent opioid analgesic used in the treatment of pain. Transdermal fentanyl patches are now widely utilized as an acceptable and efficacious method of medication delivery. Unfortunately, the potential for their abuse is well recognized. Previous case reports have documented deaths after intravenous (IV) misuse of fentanyl which had been extracted from Duragesic (liquid reservoir type) patches. We present a case of IV fentanyl abuse after the extraction from a Mylan (matrix type) patch. This method of abuse has not previously been described in the literature.