A search for missing radio sources at z>4 using Lyman dropouts

Using the Lyman Dropout technique, we identify 148 candidate radio sources at z ≳ 4-7 from the 887.5 MHz Australian Square Kilometre Array Pathfinder (ASKAP) observations of the GAMA23 field. About 112 radio sources are currently known beyond redshift z ∼4. However, simulations predict that hundreds of thousands of radio sources exist in that redshift range, many of which are probably in existing radio catalogues, but do not have measured redshifts, either because their optical emission is too faint or because of the lack of techniques that can identify candidate high-redshift radio sources (HzRSs). Our study addresses these issues using the Lyman Dropout search technique. This newly built sample probes radio luminosities that are 1-2 orders of magnitude fainter than known radio-active galactic nuclei (AGN) at similar redshifts, thanks to ASKAP's sensitivity. We investigate the physical origin of radio emission in our sample using a set of diagnostics: (i) radio luminosity at 1.4 GHz, (ii) 1.4 GHz to 3.4 μm flux density ratio, (iii) Far-IR detection, (iv) WISE colour, and (v) SED modelling. The radio/IR analysis has shown that the majority of radio emission in the faint and bright end of our sample's 887.5 MHz flux density distribution originates from AGN activity. Furthermore, ∼10 per cent of our sample are found to have a 250 μm detection, suggesting a composite system. This suggests that some high-z radio-AGNs are hosted by SB galaxies in contrast to low-z radio-AGNs, which are usually hosted by quiescent elliptical galaxies

Clinical significance of recurrent venous thromboembolism Significância clínica de tromboembolismo venoso recorrente

Recurrent venous thromboembolism is a significant problem leading to increased morbidity and mortality. It has a high impact on patients' quality of life and imposes a great financial burden on society. Cumulative recurrence has been reported as 40% at 10 years, while the chance of developing postthrombotic signs and symptoms in the lower extremities almost quadruples when ipsilateral. There is also a higher chance of developing pulmonary hypertension. Important factors for recurrence are unprovoked episodes of deep vein thrombosis, malignancy and older age. The evidence for other factors is controversial. Accurate diagnosis and treatment tailored to the patients' history, thrombotic events and risk factors are necessary to optimize management and prevent recurrence.<br>O tromboembolismo venoso recorrente é um problema importante que leva ao aumento da morbimortalidade. Impõe forte impacto à qualidade de vida dos pacientes e grande carga financeira para a sociedade. Acredita-se que a recorrência cumulativa atinja 40% em 10 anos, enquanto que a chance de desenvolver sinais e sintomas pós-trombóticos nas extremidades inferiores quase quadruplica no caso de trombose ipsilateral. Há também uma maior chance do desenvolvimento de hipertensão pulmonar. Fatores importantes para a recorrência são: episódios não provocados de trombose venosa profunda, malignidade e idade avançada. As evidências relacionadas a outros fatores são controversas. Diagnóstico preciso e tratamento adaptado ao histórico dos pacientes, aos eventos trombóticos e aos fatores de risco são necessários para otimizar o manejo e prevenir a recorrência