Graphic summary
  • Show / hide key
  • Information


Scientific and technological production
  •  

1 to 50 of 87 results
  • Contactless electrical bioimpedance system for monitoring ventilation. A biodevice for vehicle environment

     Macias Macias, Raul; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Bragos Bardia, Ramon; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Nowadays, automotive companies are focused in improving road traffic safety. For that, not only the vehicle performance is improved but also the driver behavior is monitored. This could be done in many ways. One of them is to monitor a specific physiological parameter using a biodevice. That device should be reliable enough to use in a very noisy environment like a vehicle is. Furthermore, because long-term monitoring is required, any invasive and annoying method should be avoided. Therefore, an electrical bioimpedance device capable of monitoring driver ventilation using several textiles electrodes has been designed and implemented.

  • Differences in QRS locations due to ECG lead: relationship with breathing

     Garcia Gonzalez, Miquel Angel; Argelagós Palou, Ariadna; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Mediterranean Conference on Medical and Biological Engineering and Computing
    Presentation's date: 2013-09-27
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Results of heart rate variability analysis depend on the accuracy of the RR time series that is measured only in one lead of the ECG. RR time series can subtly change from lead to lead. We have obtained the ECG of 21 healthy subjects in a quiet measurement, sampled at 5 kHz and from the I and II standard leads. For each subject a total of 60 minutes was measured. The QRS complexes in both leads have been detected using a conventional QRS detector plus a further refinement using a matching template. Differences between the locations of the QRS complexes have been quantified and compared with the breathing signal of each subject as well as the derived RR time series. The typical uncertainty in the fiducial points and RR time series is usually below 1 ms and the errors are modulated by breathing.

  • Synchrosqueezing index for detecting drowsiness based on the respiratory effort signal

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; De Rosario, H.; Ramos Castro, Juan Jose
    Mediterranean Conference on Medical and Biological Engineering and Computing
    Presentation's date: 2013-09-27
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Objective: The aim of this work is to evaluate a new index to assess the alertness state of drivers based on the respiratory dynamics derived from an inductive band using the variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ). Background: Biomedical variables like abdominal effort, which is related to autonomic nervous system, provides direct information of the driver physiological state, instead of indirect indicia of the participant's behavior. Method: The respiration data used in this study was recorded by doing 18 simulator tests in a controlled scenario. In order to evaluate the viability of variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ) Mean and the Standard Deviation of the Instantaneous Respiration Frequency (MIRF and SDIRF) obtained in the analysis for awake states and drowsy states individually was calculated. Results: The results demonstrate the viability of drowsiness detection in simulator using abdominal effort signal analyzed by Synchrosqueezing based on the significant results of the statistical analysis comparing the Mean (MIRF) and de Standard Deviation (SDIRF) of both awake and drowsy intervals instantaneous respiration frequency (MIRF 0.28 Hz ± SDIRF 0.06 Hz (awake) vs. MIRF 0.21 Hz ± SDIRF 0.06 Hz (drowsy), N=18, p<0.001, t=4.88.

    Objective: The aim of this work is to evaluate a new index to assess the alertness state of drivers based on the respiratory dynamics derived from an inductive band using the variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ). Background: Biomedical variables like abdominal effort, which is related to autonomic nervous system, provides direct information of the driver physiological state, instead of indirect indicia of the participant’s behavior. Method: The respiration data used in this study was recorded by doing 18 simulator tests in a controlled scenario. In order to evaluate the viability of variability of the respiratory rhythms assessed by Synchrosqueezing (SSQ) Mean and the Standard Deviation of the Instantaneous Respiration Frequency (MIRF and SDIRF) obtained in the analysis for awake states and drowsy states individually was calculated. Results: The results demonstrate the viability of drowsiness detection in simulator using abdominal effort signal analyzed by Synchrosqueezing based on the significant results of the statistical analysis comparing the Mean (MIRF) and de Standard Deviation (SDIRF) of both awake and drowsy intervals instantaneous respiration frequency (MIRF 0.28 Hz ± SDIRF 0.06 Hz (awake) vs. MIRF 0.21 Hz ± SDIRF 0.06 Hz (drowsy), N=18, p<0.001, t=4.88.

  • Drowsiness detection by electrooculogram signal analysis in driving simulator conditions for gold standard signal generation

     Rodríguez-Ibáñez, N.; Meca-Calderón, Pablo; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Detection of drowsiness while driving is a leading objective in advanced driver assistance systems. This work presents a new index to assess the alertness state of drivers based on the EOG dynamics derived from a polysomnography device. More than 15 hours of laboratory tests were analyzed in order to detect drowsiness while doing cognitive activities. The proposed method has a sensitivity of 92, 41% and a VPP of 93,41% in detecting drowsiness. The results show that the proposed index may be promising to assess the alertness state of real drivers

  • Access to the full text
    Using smartphone bases biodevices for analyzing physiological, psychological and behavioral user¿s habits  Open access

     Guede Fernandez, Federico; Pous Sola, Marc; Garcia Gonzalez, Miquel Angel; Capdevila Ortis, Lluís; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Biomedical Electronics and Devices
    Presentation's date: 2013-02
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    As a consequence of increasing life expectancy, the promotion of lifestyles that allow aging wellbeing guarantees has acquired great importance in the developed countries. However, the adherence to healthy behaviors in young and adult people remains as a big problem in the community health field. The development of markers of adherence to healthy lifestyles and the evaluation its effectiveness is a goal of many research groups. This paper presents a system for analyzing physiological, psychological and behavioural user’s habits using a smartphone and externals biodevices. We use an Android smartphone with an internal tri-axial accelerometer and GPS to monitor physical activity. The smartphone is connected via Bluetooth to a respiratory sensor for breath monitoring. In addition, Android application contains psychological questionnaires to analyze user’s mood state and at the same, social interaction is analyzed tracking phone usage and user’s social network. Finally, the collected information is sent to a remote server for a long-term processing.

  • A comparison of heartbeat detectors for the seismocardiogram

     Garcia Gonzalez, Miquel Angel; Argelagós Palou, Ariadna; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Computing in Cardiology
    Presentation's date: 2013-09-24
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The study aimed to study the accuracy in RR time series derived from the seismocardiogram when employing different heartbeat detectors in subjects measured in a quiet environment. The ECG and seismocardiogram of 17 healthy volunteers was recorded at a sampling frequency of 5 kHz using a Biopac acquisition system. The seismocardiogram was acquired using a triaxial accelerometer (LIS344ALH, ST Microelectronics). Four detectors of the heartbeat from the seismocardiogram were employed relying either on the Continuous Wavelet Transform or bandpass filtering. The detectors adapt their parameters to the morphology of the signal by estimating mean heart rate and the bandwidth of the signal associated to the heartbeat. For all detectors, the standard deviation of the error in the obtained RR time series is in mean slightly higher than 2 ms and the percentage of obtained RR time intervals that have an error higher than 30 ms is around 3.5%. The seismocardiogram, when measured in a quiet environment, can be used instead of the ECG to obtain reliable RR time series when using proper heartbeat detectors.

  • An application of fractional differintegration to heart rate variability time series

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Capdevila, Lluis; Parrado, Eva
    Computer methods and programs in biomedicine
    Date of publication: 2013-07
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Fractional differintegration is used as a new tool to characterize heart rate variability time series. This paper proposes and focuses in two indexes (ac and fnQ) derived from the fractional differintegration operator. Both indexes are applied to fractional Gaussian noise (fGn) and actual RR time series in order to test their behavior. In the analysis of monofractal time series, ac is linearly related with the Hurst exponent and the estimation of the exponent by the proposed index has lower variance than by using Detrended Fluctuation Analysis (DFA) or the periodogram. The other index fnQ quantifies how the time series adjust to a monofractal time series. Age, postural changes and paced breathing cause significant changes on fnQ while ac only shows significant changes due to posture. In the analyzed actual HRV time series, ac shows good correlation with the short term scaling exponent obtained by DFA, LF/HF and RMSSD while no correlations have been found for fnQ.

  • Desenvolupament de marcadors d'estil de vida saludable per a gent grant basats en Smartphones

     Garcia Gonzalez, Miquel Angel
    Participation in a competitive project

     Share

  • A wireless under-mattress sensor system for sleep monitoring in people with major depression

     Mahdavi, Hadiseh; Ramos Castro, Juan Jose; Giovinazzo, Giuseppe; Garcia Gonzalez, Miquel Angel; Rosell Ferrer, Francisco Javier
    IASTED International Conference Biomedical Engineering
    Presentation's date: 2012-02-16
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Monitoring people during sleep time is of particular interest to patients with sleep disorders and elderly people or infants. We have developed a battery powered electronic system to monitor people in the bed, store the data and send them through a wireless link to a PC. The resulting data will be subject to further analysis using pattern recognition to evaluate the feasibility of using the system as an indicator of sleep quality. The system is able to detect presence on the bed and movements and breathing of the patient. The changes in pressure distribution on the mattress cause changes in pressure in the layers of the sensor and a voltage will appear on the electrodes. The detection ability depends strongly on the shape of the mattress and the bedbase.

  • Improvement of the actimetry agreement among sites by proper choice of signal processing stages

     Garcia Gonzalez, Miquel Angel; Giovinazzo, Giuseppe; Gomez Bule, Rafael; Landi, Francesca; Ramos Castro, Juan Jose; Rosell Ferrer, Francisco Javier
    IASTED International Conference Biomedical Engineering
    Presentation's date: 2012-02-15
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Physical activity (PA) has been identified as a key health indicator and has been assessed in multiple studies as the study of cardiovascular diseases, diabetes mellitus, obesity and psychological conditions. For this reason the use of accelerometers to quantify PA is widely accepted in either clinical/laboratory settings as well as in freeliving environments. The use of accelerometers in the measurement of PA is a relatively new technique and, therefore, has been not standardized. The aim of this work is to study the influence of signal processing stages in the estimation of PA while measuring simultaneously in three different sites to provide robust indicators of activity in front of changes in site measurement. With our measurement we show that a proper choice of signal processing steps can improve the agreement among activity indices measured from different sites on the same individual. The results also show that the most suited index is the time above threshold. In this case, the best combination of axes is by applying the quadratic mean, the best filtering of axes is using a cut-off frequency of around 1.5 Hz and a threshold to compute the index of 0.04 g.

  • Changes in heart rate variability indexes due to drowsiness in professional drivers measured in a real environment

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose; Rodríguez Ibáñez, Noelia; de la Cruz, M.A.F.
    Computing in Cardiology
    Presentation's date: 2012-09-12
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The study aims to assess the changes in Heart Rate Variability (HRV) indexes in healthy subjects whi le driving in a real environment in order to detect drowsiness. The ECG of ten professional drivers was acquired while driving on routes familiar to the subjects. RR time series were quantified using a sliding window of 300 beats. Mean (mRR), standard devi ation (SDNN), standard deviation of the differentiated time series (rmsDD), power of the low (PLF) and high (PHF) frequency bands as well as the ratio LF/HF were computed. In addition, the median frequency of the power spectrum (MEDF), the bandwidth that c ontains the 50% of the power (BW50) and a measure of the asymmetry of the spectrum (AFS) were obtained. Moreover, the Hurst exponent estimated by fractional differintegration (HFDI) and the short scaling exponent obtained by detrended fluctuation analysis (α 1 ) were computed. Two observers classified the state of the drivers minute by minute by inspection of video recordings as alert or drowsy driver. Five subjects were alert for the whole recording while the others presented one or more periods of drowsines s in seven recordings between resting stops. There are not significant differences between groups for all indexes but BW50 (p<0.05). Nevertheless paired tests comparing drowsy and alert periods show significant differences (p<0.05) for SDNN, HFDI, mRR, BW 50 , AFS, α 1 , LF/HF and MEDF.

  • Unobtrusive activity measurement in patients with depression: the H4M approach

     Ramos Castro, Juan Jose; Mahdavi, Hadiseh; Pérez Diaz de Cerio, David; Garcia Gonzalez, Miquel Angel; Estevez, Soraya; Rosell Ferrer, Francisco Javier
    Information and Communication Technologies applied to Mental Health
    Presentation's date: 2012-10-04
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • A novel index based on fractional calculus to assess the dynamics of heart rate variability: changes due to chi or yoga meditations

     Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    Computing in Cardiology
    Presentation's date: 2012-09-12
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The study aims to present and interpret a novel index based on fractional calculus (c) and to assess differences in RR time series dynamics in subjects during meditation. Fractional differintegration (FDI) of a RR time series provides a new time series. c is defined as the order of the FDI operator that provides the time series with minimum variance. Analyzed time series were obtained from the Exaggerated Heart Rate Oscillations During Two Meditation Techniques database. This database contains RR time series before and after Chi Meditation and Kundalini Yoga. It also contains recordings of elite athletes and healthy subjects while sleeping and during metronomic breathing at 0.25 Hz. c is significantly higher during Chi or Yoga meditation when compared with the recordings before the meditation starts or in subjects while sleeping or during metronomic breathing. 2012 CCAL.

    The study aims to present and interpret a novel index based on fractional calculus ( αc) and to assess differences in RR time series dynamics in subjects during meditation. Fractional differintegration (FDI) of a RR time series provides a new time series.αc is defined as the order of the FDI operator that provides the time series with minimum variance. Analyzed time series were obtained from the Exaggerated Heart Rate Oscillations During Two Meditation Techniques database. This database contains RR time series before and after Chi Meditation and Kundalini Yoga. It also contains recordings of elite athletes and healthy subjects while sleeping and during metronomic breathing at 0.25 Hz. αc is significantly higher during Chi or Yoga meditation when compared with the recordings before the meditation starts or in subjects while sleeping or during metronomic breathing.

  • Heart rate variability analysis using a seismocardiogram signal

     Ramos Castro, Juan Jose; Moreno, J.; Miranda-Vidal, H.; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Rodas, G.; Capdevila, L.
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2012-08-31
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Seismocardiography is a simple and non invasive method of recording cardiac activity fro m the movements of the body caused by heart pumping. In this preliminary study we use a smartphone to record this acceleration and estimate the heart rate. We compare the heart rate variability parameters from the seismocardi ogram and ECG reference signal. The results show a great similarity and are strongly influenced by the instability in the sampling frequency of the device. The differences between RR series are lower than 10 ms.

  • Development of a system to test somnolence detectors with drowsy drivers

     Lopez De la O, Jaime; Rodríguez Ibáñez, Noelia; Nombela, Mario; Barrios, Jose Manuel; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    Procedia - Social and behavioral sciences
    Date of publication: 2012
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Somnolence; Semi-autonomous conduction

  • Sistema combinado de análisis de parámetros fisiológicos, cognitivos y conductuales basado en plataformas móviles

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose
    Participation in a competitive project

     Share

  • Drowsiness detection by thoracic effort signal analysis in real driving environments

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2011-09-02
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Detection of drowsiness while driving is a leading objective in advanced driver assistance systems. This work presents a new index to assess the alertness state of drivers based on the respiratory dynamics derived from an inductive band. More than 100 hours of driving in real environments from 13 healthy subjects were analyzed. The proposed method has a sensitivity of 93.7% and specificity of 86.3% in detecting full awake drivers while it has a sensitivity of 83.1% and specificity of 95.3% in detecting drowsy drivers. The results show that the proposed index may be promising to assess the alertness state of real drivers.

  • The Effect of Electrocardiographic Lead Choice on RR Time Series

     Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    IEEE Engineering in Medicine and Biology Society
    Presentation's date: 2011-08-31
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Results of heart rate variability analysis depend on the quality of the initial RR time series that is measured only in one lead of the ECG. This work shows that RR time series can subtly change from lead to lead so the choice of the analyzed lead is another source of uncertainty. The standard deviation of the differences of two RR time series obtained from different leads can change from 0.5 ms to more than 20 ms depending on the amount of noise, the morphological changes of the QRS complexes, the strategies of fiducial point determination and the measured subject. This source of uncertainty is in healthy subjects greater than that associated to the sampling frequency of the ECG for sampling frequencies greater than 400 Hz.

  • Access to the full text
    Drowsiness detection by thoracic effort signal snalysis with professional drivers in real environments  Open access

     Rodríguez Ibáñez, Noelia; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Fernandez Chimeno, Mireya
    International Conference on Driver Distraction and Inattention
    Presentation's date: 2011-09-06
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Objective : The aim of this work is to develop a new index to assess the alertness state of drivers based on the respiratory dynamics derived f rom an inductive band. Background : Detection of drowsiness while driving is a leadin g objective in advanced driver assistance systems. A biomedical variable like thor acic effort, which is related to autonomic nervous system, provides direct information of the driver physiological state, instead of indirect indicia of the participant's behavior. The refore, they may be especially useful to collect detailed information of the drowsiness state and an ticipate risky situations while driving. Method : The experiment described in this paper allows us to study how drivers react in strenuous conditions, in which they tend to get fat igued and drowsy, but struggle against falling asleep. The respiration data used in this s tudy was recordered by doing 72 hours of simulation driving test and 100 hours of real vehic le tests in real environment. Results : The results demonstrate the viability of drowsine ss detection in real vehicle using thoracic effort signal. The proposed method has a s ensitivity of 93.7% and specificity of 86.3% in detecting full awake drivers while it has a sens itivity of 83.1% and specificity of 95.3% in detecting drowsy drivers. Conclusions : The proposed index may be promising to assess the alertness state of real drivers. Applications : The potential applications of the algorithm are t o detect drowsiness states while driving and give an alarm in commercial fleets or p rofessional drivers to assure the integrity of the driver.

    Postprint (author’s final draft)

  • Healthy Life style and Drowsiness Prevention-HEALING DROP

     Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya
    Participation in a competitive project

     Share

  • A COMPUTATIONAL DISTRIBUTED SYSTEM TO SUPPORT THE TREATMENT OF PATIENTS WITH MAJOR DEPRESSION

     Caminal Magrans, Pedro; Rosell Ferrer, Francisco Javier; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Mahdavi, Hadiseh
    Participation in a competitive project

     Share

  • New indices for quantification of the power spectrum of heart rate variability time series without the need of any frequency band definition

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ferrer, J; Escorihuela, R.M.; Parrado Romero, Eva; Capdevila, L; Benitez, A; Angulo, R; Rodriguez, F. A.; Iglesias, X; Bescós, R.; Marina, M; Padullés, M.; Ramos Castro, Juan Jose
    Physiological measurement
    Date of publication: 2011-06-07
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    This paper presents a new family of indices for the frequency domain analysis of heart rate variability time series that do not need any frequency band definition. After proper detrending of the time series, a cumulated power spectrum is obtained and frequencies that contain a certain percentage of the power below them are identified, so median frequency, bandwidth and a measure of the power spectrum asymmetry are proposed to complement or improve the classical spectral indices as the ratio of the powers of LF and HF bands (LF/HF). In normal conditions the median frequency provides similar information as the classical indices, while the bandwidth and asymmetry can be complementary measures of the physiological state of the tested subject. The proposed indices seem to be a good choice for tracking changes in the power spectrum in exercise stress, and they can guide in the determination of frequency band limits in other animal species.

  • Access to the full text
    A new and fast index for the quantification of short range self-similarity in RR time series  Open access

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Computing in Cardiology
    Presentation's date: 2010-09-27
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    We propose a new and very fast index (the frequency of sign changes of the mirrored differences or fscmd) with good correlation with the short range scaling exponent (  R) estimated among scales 4 to 16 of the DFA. fscmd computes the relative number of sign changes of the difference of the RR time series minus their corresponding reversed RR time series after a moving average detrending procedure is applied using a window of 30 samples. Linear regression results with simulated time series with Fractional Brownian Noise and with actual time series using the Fantasia (FT), Normal Sinus Rhythm RR time series (NSR) and Congestive Heart Failure RR interval (CHF) databases after artifact correction show good agreement between fscmd and  R. Finally, Mann-Whitney Rank Sum tests applied to  R and fscmd when comparing NSR and CHF databases show very significant differences (p<0.001) between groups for both indices.

  • Un método rápido para la cuantificación de la autosemejanza de corto alcance en series RR

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation's date: 2010-11-26
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Ventilatory threshold prediction by spectral analysis of heart rate variability in incremental maximal tests

     Benítez Herrera, Adolfo; Garcia Gonzalez, Miquel Angel; Angulo, R.; Rodríguez, F.; Iglesias, X.; Bescós, R.; Marina, M.; Padullés, M.
    Computing in Cardiology
    Presentation's date: 2010-08-29
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Comparison of omega wave system and polar S810i to detect R-R intervals at rest

     Parrado Romero, Eva; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Cervantes Blasquez, Julio Cesar; Rodas, Gil; Capdevila Orti, Lluís
    International journal of sports medicine
    Date of publication: 2010
    Journal article

     Share Reference managers Reference managers Open in new window

  • SISTEMA DE ANALISIS DE PARAMETROS FISIOLOGICOS INDICADORES DE SALUD, APLICACION A RESULTADOS EN HUMANOS Y ANIMALES

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Vargas Drechsler, Manuel Agustin; Ramos Castro, Juan Jose
    Participation in a competitive project

     Share

  • An Empirical Methodology for the Definition of Frequency Bands for Spectral Analysis of Heart Rate Variability in Animals: Application to Sprague-Dawley Rats

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Escorihuela, R.M.; Capdevila, L.; Ramos Castro, Juan Jose
    World Congress on Medical Physics and Biomedical Engineering
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Access to the full text
    Obtención empírica del límite frecuencial entre las bandas de baja y altra frecuencia en análisis de variabilidad del ritmo cardíaco: aplicación en ratas y humanos  Open access

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Escorihuela, R.M.; Capdevila, Lluis; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation's date: 2009-11
    Presentation of work at congresses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Se propone un nuevo método para la determinación empírica de los límites entre las bandas de baja frecuencia y alta frecuencia del espectro de potencia de las series RR en los estudios de variabilidad del ritmo cardíaco. El método se ha aplicado a series RR obtenidas en humanos y ratas Sprague-Dawley. Para humanos el límite coincide con la recomendación de 0,15 Hz mientras que para ratas Sprague-Dawley la metodología empleada sugiere un límite de 0,75 Hz.

  • Errors in the Estimation of Approximate Entropy and Other Recurrence-Plot-Derived Indices Due to the Finite Resolution of RR Time Series

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE transactions on biomedical engineering
    Date of publication: 2009-02
    Journal article

     Share Reference managers Reference managers Open in new window

  • Changes in myocardial electrical impedance in human heart graft rejection

     Cinca Cosculluela, Juan; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Bragos Bardia, Ramon; Bayés-Genis, Antoni; Salazar Muñoz, Yolocuauhtli; Bordes, Ramon; Campreciós, Marta; Garcia Picart, Joan; Viñolas, Xavier; Rosell Ferrer, Francisco Javier
    European journal of heart failure
    Date of publication: 2008-06
    Journal article

     Share Reference managers Reference managers Open in new window

  • Estudio de viabilidad de la medida de impedancia eléctrica para evaluar el rechazo cardíaco

     Rosell-Ferrer, J; Rosell Ferrer, Francisco Javier; Giovinazzo, G; Galvez, C; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Raga, S; Sabate, M; Cinca Cosculluela, Juan
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Cuantificación de la estabilidad de la media y la varianza en series RR: aplicación a registros en reposo y durante el ejercicio de intensidad moderada

     Garcia Gonzalez, Miquel Angel; Marine, M Ocaña; Benítez, A Herrera; Fernandez Chimeno, Mireya; Rodas, G Font; Rodríguez, F A Guisado; Ramos Castro, Juan Jose
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Normalization of the standard deviation and spectral indices of RR time series for comparison among situations with different mean heart rate

     García-González, M A; Garcia Gonzalez, Miquel Angel; Fernández-Chimeno, M; Fernandez Chimeno, Mireya; Capdevila, L; Ocaña, M; Rodas, G; Ramos Castro, Juan Jose
    European Conference of the International Federation for Medical and Biological Engineering
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Different impedance indexes in segmental and whole-body measurements in peritoneal dialysis patients

     Nescolarde Selva, Lexa Digna; Doñate, T; Garcia Gonzalez, Miquel Angel; Rosell-Ferrer, J; Rosell Ferrer, Francisco Javier
    International Conference on Electrical Bio-impedance
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Medical Equipment Immunity Assessment by Time Domain Analysis. Applications to GSM signals

     Fernández-Chimeno, M; Fernandez Chimeno, Mireya; García-González, M A; Garcia Gonzalez, Miquel Angel; Silva Martinez, Fernando
    IEEE International Symposium on Electromagnetic Compatibility
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Red de Insuficiencia Cardiaca (REDINSCOR). Red del Instituto de Salut Carlos III.

     Rosell Ferrer, Francisco Javier; Nescolarde Selva, Lexa Digna; Ramos Castro, Juan Jose; Garcia Gonzalez, Miquel Angel; Sánchez Terrones, B.; Giovinazzo, Giuseppe
    Participation in a competitive project

     Share

  • Heart Graft Rejection Assessed by Multi-Frequency Electrical Impedance: Human Results

     Rosell Ferrer, Francisco Javier; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Bragos Bardia, Ramon; Salazar, Y.; Fernandez Chimeno, Mireya; Viñolas, X.; Cinca Cosculluela, Juan
    International Conference on Electrical Bio-impedance
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Access to the full text
    Estimation of the uncertainty in time domain indices of RR time series  Open access

     Garcia-Gonzalez, M A; Garcia Gonzalez, Miquel Angel; Fernandez-Chimeno, M; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    IEEE transactions on biomedical engineering
    Date of publication: 2007-03
    Journal article

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    A method for estimating the uncertainty in time-domain indices of RR time series is described. The method relies on the central limit theorem that states that the distribution of a sample average of independent samples has an uncertainty that asymptotically approaches to the sample standard deviation divided by the square root of the number of samples. Because RR time series cannot be characterized by a set of independent samples, we propose to estimate the uncertainty of indices by computing them in blocks that satisfy that the obtained partial indices are independent. We propose a methodology to search sets of independent partial indices and apply this methodology to the estimation of the uncertainty in the mean RR, SDRR, and r-msDD indices. The results show that the uncertainty can be higher than the 10% of the index for the SDRR and even higher for the r-msDD. Moreover, a statistical test for the difference of two indices is proposed.

  • Thoracic vs Whole-Body bioimpedance measurements; relation to hydration status and hypertension in peritoneal dialysis patients

     Nescolarde Selva, Lexa Digna; García-González, M A; Garcia Gonzalez, Miquel Angel; Rosell Ferrer, Francisco Javier; Doñate, T; Querfeld, U
    Physiological measurement
    Date of publication: 2006-10
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • NOISE IN INSTRUMENTATION

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Vargas Drechsler, Manuel Agustin; Ramos Castro, Juan Jose; Miguel, A Garcia
    Date of publication: 2006-06
    Book chapter

     Share Reference managers Reference managers Open in new window

  • Medidas de "whole-body" y segmentales en pacientes en CAPD y su relación con la clínica

     Nescolarde Selva, Lexa Digna; Rosell Ferrer, Francisco Javier; Garcia Gonzalez, Miquel Angel; Doñate, T; Piccoli, A
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Bias on the approximate entropy of rr time series caused by the ecg sampling frequency

     Garcia Gonzalez, Miquel Angel; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    EMBEC'05 - 3rd European Medical and Biological Engineering Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • BIAS ON THE APPROXIMATE ENTROPY OF RR TIME SERIES CAUSED BY THE ECG SAMPLING FREQUENCY

     Garcia Gonzalez, Miquel Angel
    EMBEC'05 - 3rd European Medical and Biological Engineering Conference
    Presentation's date: 2005-11-20
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Myocardial electrical impedance spectroscopy in transplanted human heart with adn without graft rejection

     Rosell Ferrer, Francisco Javier; Bragos Bardia, Ramon; Ramos Castro, Juan Jose; Salazar, Y.; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan; Garcia Gonzalez, Miquel Angel; Vinolas, X; Rodríguez, E Font; Bayés-Genis, Antoni
    EMBEC'05 - 3rd European Medical and Biological Engineering Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Teaching measurement uncertainty to undergraduate electronic instrumentation students

     Fernandez Chimeno, Mireya; Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose
    International journal of engineering education
    Date of publication: 2005-02
    Journal article

     Share Reference managers Reference managers Open in new window

  • Endocardial impedance spectroscopy system using a transcatheter method

     Bragos Bardia, Ramon; Ramos Castro, Juan Jose; Yolocuauhtli, Salazar; Fontova, Andreu; Fernandez Chimeno, Mireya; Riu Costa, Pere Joan; Garcia Gonzalez, Miquel Angel; Bayés-Genis, Antoni; Cinca Cosculluela, Juan; Rosell Ferrer, Francisco Javier
    International Conference on Electrical Bio-impedance
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Multiparametric measurement system for detection of cardiac graft rejection

     Ramos Castro, Juan Jose; Bragos Bardia, Ramon; Garcia Gonzalez, Miquel Angel; Yolocuauhtli, Salazar; Fontova, Andreu; Bayés-Genis, Antoni; Rosell Ferrer, Francisco Javier
    IEEE Instrumentation and Measurement Technology Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Bias and uncertainty in heart rate variability spectral indices due to the finite ecg sampling frequency

     García-González, M A; Garcia Gonzalez, Miquel Angel; Fernández-Chimeno, M; Fernandez Chimeno, Mireya; Ramos Castro, Juan Jose
    Physiological measurement
    Date of publication: 2004-02
    Journal article

     Share Reference managers Reference managers Open in new window

  • Obtención del perfil de temperatura intracardíaca y su variación con la respiración en modelos procinos anestesiados

     Garcia Gonzalez, Miquel Angel; Ramos Castro, Juan Jose; Salazar, Y.; Bragos Bardia, Ramon; Bayés, A; Rosell Ferrer, Francisco Javier
    Congreso Anual de la Sociedad Española de Ingeniería Biomédica
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window