[1] We systematically used two approaches to analyze broadband seismic signals for monitoring active volcanoes: one is waveform inversion of very-long-period (VLP) signals assuming possible source mechanisms; the other is a source location method of long-period (LP) events and tremor using their amplitudes. The deterministic approach of the waveform inversion is useful to constrain the source mechanism and location but is basically only applicable to VLP signals with periods longer than a few seconds. The source location method assumes isotropic radiation of S waves and uses seismic amplitudes corrected for site amplifications. This simple approach provides reasonable source locations for various seismic signals such as a VLP event accompanying LP signals, an explosion event, and tremor associated with lahars and pyroclastic flows observed at five or fewer stations. Our results indicate that a frequency band of about 5-12 Hz and a Q factor of about 60 are appropriate for the determination of the source locations. In this frequency band the assumption of isotropic radiation may become valid because of the path effect caused by the scattering of seismic waves. The source location method may be categorized as a stochastic approach based on the nature of scattering waves. Systematic use of these two approaches provides a way to better utilize broadband seismic signals observed at a limited number of stations for improved monitoring of active volcanoes.Citation: Kumagai, H., M. Nakano, T. Maeda, H. Yepes, P. Palacios, M. Ruiz, S. Arrais, M. Vaca, I. Molina, and T. Yamashima (2010), Broadband seismic monitoring of active volcanoes using deterministic and stochastic approaches,

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Ecuador has 55 active volcanoes in the northern half of the Ecuadorian Andes. There, consequences of active volcanism include ashfalls, pyroclastic flows (fast moving fluidized material of hot gas, ash, and rock), and lahars (mudflows), which result in serious damage locally and regionally and thus are of major concern to Ecuadorians. In particular, Tungurahua (elevation, 5023 meters) and Cotopaxi (elevation, 5876 meters) are high‐risk volcanoes. Since 1999, eruption activity at Tungurahua has continued and has produced ashfalls and lahars that damage towns and villages on the flanks of the volcano. More than 20,000 people live on these flanks.

Introduction Since the coronavirus disease 2019 (COVID-19) pandemic, cardiac surgeries in patients with previous infection by COVID-19 were suspended or postponed, which led to surgeries performed in patients with an advanced stage of their disease and an increase in the waiting list. There is a heterogeneous attitude in Latin America on the optimal timing to cardiac surgery in patients with previous COVID-19 infection due to scarce data on its outcome. Two Latin American associations joined to establish common suggestions on the optimal timing of surgery in patients with previous COVID-19 infection. Methods Data collection was performed using a pre-established form, which included year of publication, objective, type of study (prospective/retrospective, descriptive/analytical), number of patients, year of study, waiting time between infection and surgery, type of surgery, morbidity, mortality, and conclusions regarding the association between mortality and morbidity. Final recommendations were approved by the board of directors of Latin American Association of Cardiac and Endovascular Surgery (LACES) and Latin American Confederation of Anesthesia Societies (CLASA). Results Of the initial 1,016 articles, 11 comprised the final selection. Only six of them included patients who underwent cardiac surgery. According to the analyzed literature, optimal timing for cardiac surgery needs to consider the following aspects: deferable surgery, symptomatic COVID-19 infection, completeness of COVID-19 vaccination. Conclusion These recommendations derive from the analysis of the scarce literature published at present on outcomes after cardiac surgery in patients with previous COVID-19 infection. These are to be taken as a dynamic recommendation in which Latin American reality was taken into consideration.

PRISMA guidelines were used for reporting the review. The evidence ranking was carried out by means of the Oxford criteria. Results: Six articles met the eligibility criteria and were included in this scoping review. Three articles were case reports, one was a review and two were original studies. For the treatment of AI, direct or indirect composite resins were the most commonly used material of choice in the retrieved studies because they demonstrate greater longevity, aesthetics and function compared to the other materials used. Conclusions:Among children and adolescents with AI, the temporary restorative treatment that demonstrated better long-term results in permanent teeth was the direct and indirect composite resins. However, high quality studies should be conducted to confirm the results presented herein.