Functional characterization of developing heart in embryos using Electric Potential Sensors

The characterization of the electrocardiographic activity of the living zebrafish heart during early developmental stages is a challenging task. Most of the available techniques are limited to heartbeat rate quantification being this inaccurate. Other invasive methodologies require the insertion of electrodes noise isolated environments and advanced amplification stages making these techniques very expensive. In this paper, we present a novel and non-invasive sensor development to characterize the functional activity of the developing heart of in vivo zebrafish embryos. The design is based on the Electric Potential Sensing technology patented at Sussex which has been developed to achieve reproducibility and continuous detection. We present preliminary functional characterization data of the developing zebrafish heart starting at 3 days-post-fertilization. Results show that using the proposed system for mapping the electrocardiographic activity of the zebrafish heart at early developmental stages is successfully accomplished. This is the first time that such a sensitive sensor has been developed for measuring the electrical changes occurring on micron sized (< 100 µm) living samples such as the zebrafish heart

An experimental method for bio-signal denoising using unconventional sensors

In bio-signal denoising, current methods reported in literature consider purely simulated envi-ronments, requiring high computational powers and signal processing algorithms that may in-troduce signal distortion. To achieve an efficient noise reduction, such methods require previous knowledge of the noise signals or to have certain periodicity and stability, making the noise es-timation difficult to predict. In this paper, we solve these challenges through the development of an experimental method applied for bio-signal denoising using a combined approach. This is based on the implementation of unconventional electric field sensors used for creating a noise replica required to obtain the ideal Wiener filter transfer function and achieve further noise reduction. This work aims to investigate the suitability of the proposed approach for the real-time noise reduction affecting bio-signal recordings. The experimental evaluation presented considers two scenarios: a) human bio-signals trials including electrocardiogram, electromyogram and elec-trooculogram; and b) bio-signal recordings from the MIT-MIH arrhythmia database. The per-formance of the proposed method is evaluated using qualitative (i.e. power spectral density) and quantitative criteria (i.e. signal-to-noise ratio and mean square error) followed by a comparison between the proposed methodology and state of the art denoising methods. The results indicate that the combined approach proposed in this paper can be used for noise reduction in electro-cardiogram, electromyogram and electrooculogram signals achieving noise attenuation levels of 26.4 dB, 21.2 dB and 40.8 dB, respectively

Neo-SENSE: a non-invasive smart sensing mattress for cardiac monitoring of babies

Within the first minute of life a newborn must take its first breath to make the transition from life inside the womb to the outside world. If a baby does not start breathing, its heart rate will drop and the circulation of blood carrying oxygen to the organs will be seriously affected. The damage done to a newborn who is deprived of oxygen happens so quickly that rapid response is imperative. During birth, the attending neonatal staff manually listen to the baby´s heart and count the heart rate; however, this has proven inaccurate and inefficient. Nowadays, there is not a reliable method to monitor newborn heart rate promptly throughout birth. In this paper, we report the design and development of a novel smart mattress device to measure the babies’ electrocardiogram and respiration non-invasively. The device is based on electrometer-based amplifier sensors combined with novel screen-printing techniques. Proof of concept tests are carried out to demonstrate the suitability of the smart-mattress for new born ECG monitoring. We perform tests with a young infant and demonstrate the potential of this sensing technology to provide a quick and reliable application as ECG readings were displayed within a time < 30 seconds. This will aid the neonatal staff to assess the success of the resuscitation technology aiming to lower the incidence of long-term consequences of poor adaptation to life outside the womb

Novel 3D printed device with integrated macroscale magnetic field triggerable anti-cancer drug delivery system

With the growing demand for personalized medicine and medical devices, the impact of on-demand triggerable (e.g., via magnetic fields) drug delivery systems increased significantly in recent years. The three-dimensional (3D) printing technology has already been applied in the development of personalized dosage forms because of its high-precision and accurate manufacturing ability. In this study, a novel magnetically triggerable drug delivery device composed of a magnetic polydimethylsiloxane (PDMS) sponge cylinder and a 3D printed reservoir was designed, fabricated and characterized. This system can realize a switch between “on” and “off” state easily through the application of different magnetic fields and from different directions. Active and repeatable control of the localized drug release could be achieved by the utilization of magnetic fields to this device due to the shrinking extent of the macro-porous magnetic sponge inside. The switching “on” state of drug-releasing could be realized by the magnetic bar contacted with the side part of the device because the times at which 50%, 80% and 90% (w/w) of the drug were dissolved are observed to be 20, 55 and 140 min, respectively. In contrast, the switching “off” state of drug-releasing could be realized by the magnetic bar placed at the bottom of the device as only 10% (w/w) of the drug could be released within 12 h. An anti-cancer substance, 5-fluorouracil (FLU), was used as the model drug to illustrate the drug release behaviour of the device under different strengths of magnetic fields applied. In vitro cell culture studies also demonstrated that the stronger the magnetic field applied, the higher the drug release from the deformed PDMS sponge cylinder and thus more obvious inhibition effects on Trex cell growth. All results confirmed that the device can provide a safe, long-term, triggerable and reutilizable way for localized disease treatment such as cancer

Characterisation of textile embedded electrodes for use in a neonatal smart mattress electrocardiography system

Heart rate monitoring is the predominant quantitative health indicator of a newborn in the delivery room. A rapid and accurate heart rate measurement is vital during the first minutes after birth. Clinical recommendations suggest that electrocardiogram (ECG) monitoring should be widely adopted in the neonatal intensive care unit to reduce infant mortality and improve long term health outcomes in births that require intervention. Novel non-contact electrocardiogram sensors can reduce the time from birth to heart rate reading as well as providing unobtrusive and continuous monitoring during intervention. In this work we report the design and development of a solution to provide high resolution, real time electrocardiogram data to the clinicians within the delivery room using non-contact electric potential sensors embedded in a neonatal intensive care unit mattress. A real-time high-resolution electrocardiogram acquisition solution based on a low power embedded system was developed and textile embedded electrodes were fabricated and characterised. Proof of concept tests were carried out on simulated and human cardiac signals, producing electrocardiograms suitable for the calculation of heart rate having an accuracy within ±1 beat per minute using a test ECG signal, ECG recordings from a human volunteer with a correlation coefficient of ~ 87% proved accurate beat to beat morphology reproduction of the waveform without morphological alterations and a time from application to heart rate display below 6 s. This provides evidence that flexible non-contact textile-based electrodes can be embedded in wearable devices for assisting births through heart rate monitoring and serves as a proof of concept for a complete neonate electrocardiogram monitoring system

Evaluation of screen-printing techniques for embedding ECG sensors in medical devices

Heart rate monitoring is the most important indicator to evaluate the clinical status of a newborn during birth. Approximately 90% of newborn infants make the transition from the intrauterine to extra uterine environment without major complications; however, the remaining 10% of newborn infants require assistance during this transition. Heart rate monitoring is required for guiding further interventions in the event of complications such as the need for resuscitation. In this work we evaluate the suitability of embedding electrometer-based-amplifier sensors employing novel screen-printing techniques into medical devices. We compare our results with traditional copper based wired electrodes. Our implementation was able to acquire electrocardiogram with enough signal to noise ratio, suitable for heart rate detection with a 1% loss of heart rate accuracy, compared with the copper-based electrodes. Our device has the potential to be embedded in devices for assisting births though heart rate monitoring

QoSatAr: a cross-layer architecture for E2E QoS provisioning over DVB-S2 broadband satellite systems

This article presents QoSatAr, a cross-layer architecture developed to provide end-to-end quality of service (QoS) guarantees for Internet protocol (IP) traffic over the Digital Video Broadcasting-Second generation (DVB-S2) satellite systems. The architecture design is based on a cross-layer optimization between the physical layer and the network layer to provide QoS provisioning based on the bandwidth availability present in the DVB-S2 satellite channel. Our design is developed at the satellite-independent layers, being in compliance with the ETSI-BSM-QoS standards. The architecture is set up inside the gateway, it includes a Re-Queuing Mechanism (RQM) to enhance the goodput of the EF and AF traffic classes and an adaptive IP scheduler to guarantee the high-priority traffic classes taking into account the channel conditions affected by rain events. One of the most important aspect of the architecture design is that QoSatAr is able to guarantee the QoS requirements for specific traffic flows considering a single parameter: the bandwidth availability which is set at the physical layer (considering adaptive code and modulation adaptation) and sent to the network layer by means of a cross-layer optimization. The architecture has been evaluated using the NS-2 simulator. In this article, we present evaluation metrics, extensive simulations results and conclusions about the performance of the proposed QoSatAr when it is evaluated over a DVB-S2 satellite scenario. The key results show that the implementation of this architecture enables to keep control of the satellite system load while guaranteeing the QoS levels for the high-priority traffic classes even when bandwidth variations due to rain events are experienced. Moreover, using the RQM mechanism the user’s quality of experience is improved while keeping lower delay and jitter values for the high-priority traffic classes. In particular, the AF goodput is enhanced around 33% over the drop tail scheme (on average)

Non-invasive sensor methods used in monitoring newborn babies after birth, a clinical perspective

Background Reducing the global new-born mortality is a paramount challenge for humanity. There are approximately 786,323 live births in the UK each year according to the office for National Statistics; around 10% of these newborn infants require assistance during this transition after birth. Each year around, globally around 2.5 million newborns die within their first month. The main causes are complications due to prematurity and during delivery. To act in a timely manner and prevent further damage, health professionals should rely on accurate monitoring of the main vital signs heart rate and respiratory rate. Aims To present a clinical perspective on innovative, non-invasive methods to monitor heart rate and respiratory rate in babies highlighting their advantages and limitations in comparison with well-established methods. Methods Using the data collected in our recently published systematic review we highlight the barriers and facilitators for the novel sensor devices in obtaining reliable heart rate measurements. Details about difficulties related to the application of sensors and interfaces, time to display, and user feedback are explored. We also provide a unique overview of using a non-invasive respiratory rate monitoring method by extracting RR from the pulse oximetry trace of newborn babies. Results Novel sensors to monitor heart rate offer the advantages of minimally obtrusive technologies but have limitations due to movement artefact, bad sensor coupling, intermittent measurement, and poor-quality recordings compared to gold standard well established methods. Respiratory rate can be derived accurately from pleth recordings in infants. Conclusion Some limitations have been identified in current methods to monitor heart rate and respiratory rate in newborn babies. Novel minimally invasive sensors have advantages that may help clinical practice. Further research studies are needed to assess whether they are sufficiently accurate, practical, and reliable to be suitable for clinical use

Electric potential sensing for electrocardiology

Electric potential sensing offers benefits over other methods of heart rate acquisition such as traditional silver chloride electrocardiogram and photoplethysmography. This talk outlines the state of the art in neonatal heart rate acquisition and and delves into some of the research work and collaborations that have been performed at the University of Sussex towards a functioning electric potential sensing prototype for use with newborns

An Experimental Method for Bio-Signal Denoising Using Unconventional Sensors

In bio-signal denoising, current methods reported in the literature consider purely simulated environments, requiring high computational powers and signal processing algorithms that may introduce signal distortion. To achieve an efficient noise reduction, such methods require previous knowledge of the noise signals or to have certain periodicity and stability, making the noise estimation difficult to predict. In this paper, we solve these challenges through the development of an experimental method applied to bio-signal denoising using a combined approach. This is based on the implementation of unconventional electric field sensors used for creating a noise replica required to obtain the ideal Wiener filter transfer function and achieve further noise reduction. This work aims to investigate the suitability of the proposed approach for real-time noise reduction affecting bio-signal recordings. The experimental evaluation presented here considers two scenarios: (a) human bio-signals trials including electrocardiogram, electromyogram and electrooculogram; and (b) bio-signal recordings from the MIT-MIH arrhythmia database. The performance of the proposed method is evaluated using qualitative criteria (i.e., power spectral density) and quantitative criteria (i.e., signal-to-noise ratio and mean square error) followed by a comparison between the proposed methodology and state of the art denoising methods. The results indicate that the combined approach proposed in this paper can be used for noise reduction in electrocardiogram, electromyogram and electrooculogram signals, achieving noise attenuation levels of 26.4 dB, 21.2 dB and 40.8 dB, respectively