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International audience; This paper presents a microwave system for heartbeat rate measurement. This system is based on using a vector network analyzer and horn antennas. The system generates a continuous wave signal toward a person's chest then the reflected signal is analyzed. The phase difference between the emitted and the reflected signals contains information about the chest movement; hence, the heartbeat rate can be extracted. In this work, several scenarios for detecting the heart activity are considered. The first scenario aims to provide a comparative study for using single-antenna and two-antennas microwave systems. Several radiated powers are considered in this scenario. Simultaneously with the microwave system, a wireless electrocardiograph is used as reference in order to determine the accuracy of the system. Measurements are performed in both cases when breathing normally and when holding the breath. The second scenario aims to test the ability of detecting the heartbeat activity of a person while moving. Measurements are performed while the subject walks towards the radar. Modeling is used for this purpose. The operating frequency used is 20 GHz in both scenarios. Signals are processed using wavelet transform and results show the ability to extract the heartbeat rate even with the presence of body movement.

International audience; This paper presents a microwave system for measuring the cardiopulmonary activity performed in two ways: by using single antenna and by using two antennas. This system generates a continuous wave signal at 20 GHz toward the target and then measure the reflected signal. The target is the person's chest set placed at a distance of 1 m. The VNA measures the phase variation between the emitted and received signals. This phase variation contains information about the movement of the chest. An electrocardiograph is used simultaneously with the system as reference in order to determine the accuracy of the VNA system. The measurements are performed for a person under two conditions: breathing normally and holding the breath. Wavelet transform is used for the processing the obtained signals and the heartbeat rate is extracted accurately.

International audience; This paper presents a microwave system for the detection of the cardiopulmonary activity. Measurements are performed at different operational frequencies and from different sides of a healthy subject who is breathing normally while sitting at 1 meter from the system. Simultaneously with the microwave system, a PC-based electrocardiograph is used in order to validate the heartbeat rate detection. Cardiopulmonary signals are processed using wavelet transforms in order to extract the heartbeat signal. The obtained results upon using the proposed system show the ability of detecting the cardiopulmonary signals at four sides of the subject, and the signal processing techniques show high accuracy in extracting the heartbeat signal and the heartbeat rate.

International audience; This paper presents a wireless measurement system for cardiopulmonary activity detection behind a wall. This system generates a continuous wave signal and is used at 2 different frequencies: 2.4 GHz and 10 GHz. The transmitted signal is directed toward the patient's chest situated at 1 m and then reflected. The radar system is based on a vector network analyzer, which measures the phase of S 21. The phase variation of S 21 contains information about heart and respiration activity. Measurements are carried out every 30 seconds, for a person sitting at a distance of 1 meter, directly in front of the system or behind a wall. Discrete wavelet transform is used as a processing technique to separate heartbeat signal from respiratory signal. The measurements were performed simultaneously with a PC-based electrocardiogram (ECG) which is used as a reference to validate the information extracted from the measured signals.

International audience; This paper presents a wireless measurement system for cardiopulmonary activity. This system generates a continuous wave signal at 2.4 GHz toward the target and then measures the reflected signal. The target is the person's chest set at a distance of 1 m. The radar system contains a vector network analyzer, which measures the phase of S 21. The phase variation of S 21 contains information about heart and respiration activity. Measurements are performed with two different conditions, while the person is holding respiration for 10 seconds and then breathing normally for the same duration. Filtering is used as processing technique to separate heartbeat signal from respiratory signal in the second case. The measurements were performed simultaneously with a PC-based electrocardiograph which is used as a reference to validate the information extracted from the measured signals.

International audience; This paper presents a wireless cardiopulmonary activity measurement system. This system generates a continuous wave toward a person's chest set at a distance of 1 m, then reflected to the system. Using a vector network analyzer, the phase of S21 is computed. The phase variation of S21 contains information about cardiopulmonary activity. Several processing techniques are used to separate heartbeat signal from cardiorespiratory signal either in frequency or in temporal domain. The measurements were performed simultaneously with a PC-based electrocardiogram to validate the heartbeat rate detection techniques. In conclusion, processing techniques used in this paper give accurate results.

AIM: To compare the efficacy of the proton-pump inhibitor, rabeprazole, with that of the H2-receptor antagonist, ranitidine, as on-demand therapy for relieving symptoms associated with non-erosive reflux disease (NERD). METHODS: This is a single center, prospective, randomized, open-label trial of on-demand therapy with rabeprazole (group A) vs ranitidine (group B) for 4 wk. Eighty-three patients who presented to the American University of Beirut Medical Center with persistent gastroesophageal reflux disease (GERD) symptoms and a normal upper gastrointestinal endoscopy were eligible for the study. Patients in group A (n = 44) were allowed a maximum rabeprazole dose of 20 mg twice daily, while those in group B (n = 39) were allowed a maximum ranitidine dose of 300 mg twice daily. Efficacy was assessed by patient evaluation of global symptom relief, scores of the SF-36 quality of life (QoL) questionnaires, total number of pills used, and number of medication-free days. RESULTS: Among the 83 patients who were enrolled in the study, 76 patients (40 in the rabeprazole group and 36 in the ranitidine group) completed the 4-wk trial. Baseline characteristics were comparable between both groups. After 4 wk, there was no significant difference in the subjective global symptom relief between the rabeprazole and the ranitidine groups (71.4% vs 65.4%, respectively; P = 0.9). There were no statistically significant differences between mean cumulative scores of the SF-36 QoL questionnaire for the two study groups (rabeprazole 22.40 ± 27.53 vs ranitidine 17.28 ± 37.06; P = 0.582). There was no significant difference in the mean number of pills used (rabeprazole 35.70 ± 29.75 vs ranitidine 32.86 ± 26.98; P = 0.66). There was also no statistically significant difference in the mean number of medication-free days between both groups. CONCLUSION: Rabeprazole has a comparable efficacy compared to ranitidine when given on-demand for the treatment of NERD. Both medications were associated with improved quality of life.