"Playing the beat": Occurrence of Bio-duck calls in Santos Basin (Brazil) reveals a complex acoustic behaviour for the Antarctic minke whale (Balaenoptera bonaerensis).

The Antarctic minke whale (Balaenoptera bonaerensis) (AMW) is one of the smallest species among baleen whales, occurring in the southern hemisphere from Antarctica to near the equator, and performing seasonal migrations from polar to tropical waters. Information about (AMW) occurrence in the winter breeding grounds is scarce, mostly coming from old records from whaling stations before the 1960's international moratorium, such as Costinha Station in Northeastern Brazil (6° S / 34° W) and some sightings from few dedicated visual surveys. Acoustic methods can provide important data on the occurrence and distribution of migratory species. This work describes the occurrence of the Antarctic minke whale through acoustic detections of their "Bioduck" vocalisations in the Santos Basin, South-Southeastern Brazil (22° and 28° S / 42° and 48° W). Data was recorded between November 12 and December 19, 2015. AMW calls were detected for 12 days. We detected and classified 9 different Bio-duck calls in Brazilian coastal waters, evidencing a highly diverse acoustic behavior for the minke whale breeding ground. This is the first attempt to describe the acoustic diversity of AMW vocalizations in lower latitudes, contributing important information for future conservation efforts and management of AMW populations and their habitat. Therefore, our study presents the foremost acoustic evidence of the Antarctic minke whale in Brazilian coastal waters.

Propriedades estatísticas de parâmetros obtidos de sinais de ultra-som Doppler / Statistical properties of parameters extracted from doppler ultrasound waveforms

A variabilidade, distribuiçäo e variaçäo longitudinal de 13 parâmetros obtidos a partir da forma de onda de velocidade de fluxo sanguíneo, medida com ultra-som Doppler na artéria femoral, foram estudados em 9 registros de longa duraçäo obtidos em 7 pacientes. Os sinais foram gravados em fita magnética, juntamente com o eletrocardiograma, e analisados em um computador digital. O processamento desses dados forneceu o coeficiente de variaçäo para cada um dos índices estudados e os graus de liberdade por ponto, extraídos a partir da funçäo de autocorrelaçäo. A influência da frequência cardíaca na variabilidade de cada um dos parâmetros foi também verificada através de técnicas de correlaçäo cruzada. Como resultado final säo fornecidos os dados necessários para o dimensionamento correto de amostras para estimaçäo de cada um dos 13 parâmetros em estudos clínicos