Power line interference filtering on surface electromyography based on the stationary wavelet packet transform

Power line interference is one of the main problems in surface electromyogram signals (EMG) analysis. In this work, a new method based on the stationary wavelet packet transform is proposed to estimate and remove this kind of noise from EMG data records. The performance has been quantitatively evaluated with synthetic noisy signals, obtaining good results independently from the signal to noise ratio (SNR). For the analyzed cases, the obtained results show that the correlation coefficient is around 0.99, the energy respecting to the pure EMG signal is 98–104%, the SNR is between 16.64 and 20.40 dB and the mean absolute error (MAE) is in the range of −69.02 and −65.31 dB. It has been also applied on 18 real EMG signals, evaluating the percentage of energy respecting to the noisy signals. The proposed method adjusts the reduction level to the amplitude of each harmonic present in the analyzed noisy signals (synthetic and real), reducing the harmonics with no alteration of the desired signal.

Clay minerals in the Norwegian Sea and Fram Strait, investigation from sediment traps and cores

The grain size distribution and clay mineral composition of lithogenic particles of ice-rafted material, sinking matter, surface sediments, as well as from deep-sea cores are analysed. The samples were collected in the Fram Strait, the Arctic Ocean, and the Norwegian Sea during several expeditions with the research vessels "Polarstern", "Meteor" and "Poseidon", and Norwegian rearch vessels. Sinking matter was caught with sediment traps, fitted with timer-controlled sample changers, which had been deployde in the sea for usually one year.

Hispania Damiani a Goes ...

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Annual Report of Energy Purchased by REA Borrowers

1952/53- issued as REA Bulletin 111-2

Early cognitive profiles of emergent readers:a longitudinal study

This longitudinal study examined the contribution of phonological awareness, phonological memory, and visuospatial ability to reading development in 142 English-speaking children from the start of kindergarten to the middle of Grade 2. Partial cross-lagged analyses revealed significant relationships between early performance on block design and matching letter-like forms tasks and later reading ability. Rhyme awareness correlated with later reading ability during the earliest stages, but onset awareness did not emerge as important until after the children had started reading. Digit span correlated significantly with future reading ability at every stage. These findings indicate that although phonological awareness, phonological memory, and visuospatial ability are all necessary for emergent reading, their relative importance varies across the first 2 years of reading development.