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The Help4Mood EU FP7 project (H4M) [1] proposes to significantly advance the state-ofthe-art in computerized support for people with Major Depression by monitoring mood, physical activity and voice characteristics while promoting activities in reaction to examined inputs. Employing actigraphy can provide supplementary data about patients with depression. Nonetheless, its use is not standardized and there is a lack of public analyses about treated patients with depression using this technique, which is the objective of the project. The purpose of the Personal Monitoring System (PMS) used in H4M is to compile objective data about the changes and trends of activity patterns during long periods of time. This would comprise daily activity, rest time and, if possible, sleep quality. The PMS uses inconspicuous methods but keeping the cost associated with sensor installation at the patient¿s home to a minimum. This work focuses on the Wireless Sensor Network (WSN) enhancements introduced after real testbeds and considering User Quality of Experience (QoE), mainly oriented to reduce energy consumption and required data transmission and consequently improving the autonomy and range of the sensors.

In this study, the electrical impedance of myocardial tissue is measured dynamically during the cardial cycle. The multisine-based approach used to perform electrical impedance spectroscopy (EIS) measurements allows acquiring complete spectral impedance information of the tissue dynamics during contraction. Measurements are performed in situ in the left ventricule of swines during contractility stress tests induced by dobutamine infusion. Additionally, the ECG and the left ventricular (LV) pressure are also acquired synchronously to the impedance signals. The calculated impedance magnitude exhibits a periodic behavior during tissue contraction. The amplitude (peak-to-peak) of this signal is quantified and the compared to the maximum first derivative of the LV pressure (dP/dtmax) that is used as an indicator of contractility variations. The results show a linear correlation between impedance amplitude and dP/dtmax during dobutamine-increased contractility. The present work demonstrates how fast EIS measurements during heart contraction can represent a feasible method to assess changes in myocardial contractility.