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This paper illustrates the application of the discrete wavelet transform (DWT) for wandering and noise suppression in electrocardiographic (ECG) signals. A novel one-step implementation is presented, which allows improving the overall denoising process. In addition an exhaustive study is carried out, defining threshold limits and thresholding rules for optimal wavelet denoising using this presented technique. The system has been tested using synthetic ECG signals, which allow accurately measuring the effect of the proposed processing. Moreover, results from real abdominal ECG signals acquired from pregnant women are presented in order to validate the presented approach.

In this paper, some experiments about thermal sensors based on ring-oscillator in low-voltage Virtex series FPGAs are presented. A non linear effect in the frequencytemperature response has been detected, and the sensibility of frequency with respect to voltage variations is greater than the measured in previous works. A quadratic polynomial function fits better the sensor response, and an increment in the number of inverters in the oscillator is effective to reduce the voltage sensibility.

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Flexible electronics is one of the fundamental technologies for the development of electronic skin, implant wearables, or ubiquitous biosensing. In this context, graphene-derived materials have attracted great interest due to their unique properties to fulfill the demands of these applications. Here we report a simple one-step method for the fabrication of electrophysical electrodes based on the photothermal production of porous nanographene structures on the surface of flexible polyimide substrates. This approach constitutes an inexpensive alternative to the commercial medical electrodes, leading to a lower and much more stable skin–electrode contact resistance and providing comparable signal transduction. This technology has been framed inside the IoT paradigm through the development of a denoising and signal classification clustering algorithm suitable for its implementation in wearable devices. The experiments have shown promising achievements regarding noise reduction, increasing the crest factor ~3.7 dB, as well as for the over 90% heart rate-monitoring accuracy.

The stereoselective synthesis of the naturally occurring lactones osmundalactone (−)-1 and muricatacin (−)-2 is described. The key steps in each synthesis are the stereoselective addition of a Grignard reagent to a suitably protected α-hydroxy aldehyde and a ring-closing metathesis.