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1.
Article in English | MEDLINE | ID: mdl-25570893

ABSTRACT

The objective of the INTERACTION Eu project is to develop and validate an unobtrusive and modular system for monitoring daily life activities, physical interactions with the environment and for training upper and lower extremity motor function in stroke subjects. This paper describes the development and preliminary testing of the project sensing platform made of sensing shirt, trousers, gloves and shoes. Modular prototypes were designed and built considering the minimal set of inertial, force and textile sensors that may enable an efficient monitoring of stroke patients. The single sensing elements are described and the results of their preliminary lab-level testing are reported.


Subject(s)
Activities of Daily Living , Monitoring, Physiologic/instrumentation , Stroke/physiopathology , Electrodes , Electromyography , Humans , Lower Extremity/physiology , Movement , Upper Extremity/physiology
2.
Neural Netw ; 24(7): 679-85, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21441011

ABSTRACT

Experimental evidences on the role of the synaptic glia as an active partner together with the bold synapse in neuronal signaling and dynamics of neural tissue strongly suggest to investigate on a more realistic neuron-glia model for better understanding human brain processing. Among the glial cells, the astrocytes play a crucial role in the tripartite synapsis, i.e. the dressed neuron. A well-known two-way astrocyte-neuron interaction can be found in the literature, completely revising the purely supportive role for the glia. The aim of this study is to provide a computationally efficient model for neuron-glia interaction. The neuron-glia interactions were simulated by implementing the Li-Rinzel model for an astrocyte and the Izhikevich model for a neuron. Assuming the dressed neuron dynamics similar to the nonlinear input-output characteristics of a bipolar junction transistor, we derived our computationally efficient model. This model may represent the fundamental computational unit for the development of real-time artificial neuron-glia networks opening new perspectives in pattern recognition systems and in brain neurophysiology.


Subject(s)
Astrocytes/physiology , Computer Simulation , Models, Neurological , Neurons/physiology , Synaptic Transmission/physiology , Humans , Synapses/physiology
3.
Article in English | MEDLINE | ID: mdl-21096696

ABSTRACT

This paper describes the design, the development and the preliminary testing of a wearable system able perform a real time estimation of the local curvature and the length of the spine lumbar arch. The system integrate and fuse information gathered from textile based piezoresistive sensor arrays and tri-axial accelerometers. E-textile strain sensing garments suffer from non-linearities, hysteresis and long transient, while accelerometers, used as inclinometers, present biased values and are affected by the system acceleration due to subject movements. In this work, focused on the wearability and comfort of the user, we propose a fusion of the information deriving from the two class of sensors to reduce their intrinsic errors affecting measurements. Comparative evaluation of system performances with stereophotogrammetric techniques shows a 2% error in lumbar arch length reconstruction.


Subject(s)
Biosensing Techniques/methods , Monitoring, Ambulatory/methods , Spinal Curvatures , Textiles , Equipment Design , Humans
4.
IEEE Trans Inf Technol Biomed ; 14(3): 702-10, 2010 May.
Article in English | MEDLINE | ID: mdl-20378475

ABSTRACT

The current state of the art in wearable electronics is the integration of very small devices into textile fabrics, the so-called ¿smart garment.¿ The ProeTEX project is one of many initiatives dedicated to the development of smart garments specifically designed for people who risk their lives in the line of duty such as fire fighters and Civil Protection rescuers. These garments have integrated multipurpose sensors that monitor their activities while in action. To this aim, we have developed an algorithm that combines both features extracted from the signal of a triaxial accelerometer and one ECG lead. Microprocessors integrated in the garments detect the signal magnitude area of inertial acceleration, step frequency, trunk inclination, heart rate (HR), and HR trend in real time. Given these inputs, a classifier assigns these signals to nine classes differentiating between certain physical activities (walking, running, moving on site), intensities (intense, mild, or at rest) and postures (lying down, standing up). Specific classes will be identified as dangerous to the rescuer during operation, such as, ¿subject motionless lying down¿ or ¿subject resting with abnormal HR.¿ Laboratory tests were carried out on seven healthy adult subjects with the collection of over 4.5 h of data. The results were very positive, achieving an overall classification accuracy of 88.8%.


Subject(s)
Emergency Medical Technicians , Heart Rate/physiology , Monitoring, Ambulatory/methods , Rescue Work , Signal Processing, Computer-Assisted , Adult , Algorithms , Clothing , Electrocardiography/methods , Humans , Kinetocardiography/methods , Locomotion/physiology , Male , Motor Activity/physiology
5.
Bioinspir Biomim ; 3: 016004, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18364563

ABSTRACT

The increasing complexity of the artificial implementations of biological systems, such as the so-called electronic noses (e-noses) and tongues (e-tongues), poses issues in sensory feature extraction and fusion, drift compensation and pattern recognition, especially when high reliability is required. In particular, in order to achieve effective results, the pattern recognition system must be carefully designed. In order to investigate a novel biomimetic approach for the pattern recognition module of such systems, the classification capabilities of an artificial model inspired by the mammalian cortex, a cortical-based artificial neural network (CANN), are compared with several artificial neural networks present in the e-nose and e-tongue literature, a multilayer perceptron (MLP), a Kohonen self-organizing map (KSOM) and a fuzzy Kohonen self-organizing map (FKSOM). Each network was tested with large datasets coming from a conducting polymer-sensor-based e-nose and a composite array-based e-tongue. The comparison of results showed that the CANN model is able to strongly enhance the performances of both systems.


Subject(s)
Artificial Intelligence , Biomimetics/methods , Cerebral Cortex/physiology , Models, Neurological , Nerve Net/physiology , Pattern Recognition, Automated/methods , Pattern Recognition, Physiological/physiology , Animals , Computer Simulation , Humans , Neural Networks, Computer
6.
Article in English | MEDLINE | ID: mdl-19163907

ABSTRACT

The present status of the project aimed at the realization of an innovative wearable system-on-chip UWB radar for the cardiopulmonary monitoring is presented. The overall system consists of a wearable wireless interface including a fully integrated UWB radar for the detection of the heart beat and breath rates, and a IEEE 802.15.4 ZigBee low-power radio interface. The principle of operation of the UWB radar for the monitoring of the heart wall is summarized. With respect to the prior art, this paper reports the results of the experimental characterization of the intra-body channel loss, which has been carried out successfully in order to validate the theoretical model employed for the radar system analysis. Moreover, the main building blocks of the radar have been manufactured in 90 nm CMOS technology by ST-Microelectronics and the relevant performance are resulted in excellent agreement with those expected by post-layout simulations.


Subject(s)
Clothing , Electrocardiography/instrumentation , Monitoring, Ambulatory/instrumentation , Radar/instrumentation , Spirometry/instrumentation , Telemetry/instrumentation , Electrocardiography/methods , Electrocardiography/trends , Electronics, Medical/instrumentation , Electronics, Medical/trends , Equipment Design , Equipment Failure Analysis , Heart Rate/physiology , Humans , Miniaturization , Monitoring, Ambulatory/methods , Monitoring, Ambulatory/trends , Reproducibility of Results , Respiratory Mechanics/physiology , Sensitivity and Specificity , Spirometry/methods , Spirometry/trends , Telemetry/trends
7.
Article in English | MEDLINE | ID: mdl-19162822

ABSTRACT

The paper reports the present status of the project aimed at the realization of a wearable low-cost low-power System-on-Chip (SoC) 13-GHz passive microwave radiometer in CMOS 90 nm technology. This sensor has been thought to be inserted into the firemen jacket in order to help them in the detection of a hidden fire behind a door or a wall, especially where the IR technology fail. With respect of the prior art, the SoC is further developed and a proof of the concept is provided by means of a discrete-component prototype.


Subject(s)
Environmental Monitoring/instrumentation , Fires , Protective Clothing , Radiometry/instrumentation , Rescue Work/methods , Signal Processing, Computer-Assisted/instrumentation , Transducers , Environmental Monitoring/methods , Equipment Design , Equipment Failure Analysis , Microwaves , Pilot Projects , Radiometry/methods , Reproducibility of Results , Sensitivity and Specificity
8.
Article in English | MEDLINE | ID: mdl-18003310

ABSTRACT

The remote sensing and the detection of events that may represent a danger for human beings have become more and more important thanks to the latest advances of the technology. A microwave radiometer is a sensor capable to detect a fire or an abnormal increase of the internal temperature of the human body (hyperthermia), or an onset of a cancer, or even meteorological phenomena (forest fires, pollution release, ice formation on road pavement). In this paper, the overview of a wearable low-cost low-power system-on-a-chip (SoaC) 13 GHz passive microwave radiometer in CMOS 90 nm technology is presented. In particular, we focused on its application to the fire detection for civil safeguard. In detail, this sensor has been thought to be inserted into the fireman jacket in order to help the fireman in the detection of a hidden fire behind a door or a wall. The simulation results obtained by Ptolemy system simulation have confirmed the feasibility of such a SoaC microwave radiometer in a low-cost standard silicon technology for temperature remote sensing and, in particular, for its application to the safeguard of emergency operators.


Subject(s)
Clothing , Emergency Medicine/instrumentation , Monitoring, Ambulatory/instrumentation , Protective Devices , Telemetry/instrumentation , Thermography/instrumentation , Thermometers , Equipment Design , Equipment Failure Analysis , Miniaturization , Monitoring, Ambulatory/methods , Radiometry/instrumentation , Systems Integration , Thermography/methods
9.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1858-61, 2006.
Article in English | MEDLINE | ID: mdl-17945676

ABSTRACT

In this paper we report on results from experiments performed on a bi-modal piezoelectric transducer used both as an active ultrasound transceiver and a passive acoustic sensor. The transducer, which has a low Q factor in order to exhibit a sufficiently broad bandwidth, will be integrated into a wearable system. In particular, it is placed, along with ECG fabric electrodes, within a textile belt wrapped around the chest. The transducer behaves as an acoustic sensor at low frequency and as an ultrasound transducer at high frequency. The low-frequency acoustic signals were compared with the analogue signals acquired simultaneously by commercial biomedical sensors. These signals provide information about the respiratory activity and heart apex pulse. A comparative analysis was performed both in the time and frequency domain and results were discussed. Moreover, the same transducer used at high frequencies is able to generate ultrasound signals which can bounce off the target organ, the heart, and receive the back-propagated echoes. The experimental validation was done by means of a comparison between the spatial interval inferred from time delay of the return echoes detected by the transducer and the actual distance from the target. This information, in addition to ECG signals, can provide helpful cues for the cardiac status of the subject, both in terms of prevention and diagnosis.


Subject(s)
Acoustics/instrumentation , Blood Pressure Determination/instrumentation , Monitoring, Ambulatory/instrumentation , Respiratory Function Tests/instrumentation , Respiratory Mechanics/physiology , Transducers , Ultrasonography/instrumentation , Blood Pressure Determination/methods , Equipment Design , Equipment Failure Analysis , Humans , Monitoring, Ambulatory/methods , Pilot Projects , Reproducibility of Results , Respiratory Function Tests/methods , Sensitivity and Specificity
10.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 3391-4, 2006.
Article in English | MEDLINE | ID: mdl-17946178

ABSTRACT

Electrocardiographic (ECG) signals are affected by several kinds of artifacts, that may hide vital signs of interest. Motion artifacts, due to the motion of the electrodes in relation to patient skin, are particularly frequent in bioelectrical signals acquired by wearable systems. In this paper we propose different approaches in order to get rid of motion confounds. The first approach we follow starts from measuring electrode motion provided by an accelerometer placed on the electrode and use this measurement in an adaptive filtering system to remove the noise present in the ECG. The second approach is based on independent component analysis methods applied to multichannel ECG recordings; we propose to use both instantaneous model and a frequency domain implementation of the convolutive model that accounts for different paths of the source signals to the electrodes.


Subject(s)
Electrocardiography/statistics & numerical data , Algorithms , Biomedical Engineering , Electrodes , Humans , Models, Statistical , Motion , Signal Processing, Computer-Assisted
11.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 7349-52, 2005.
Article in English | MEDLINE | ID: mdl-17281978

ABSTRACT

A wearable system able to monitor cardiopulmonary vital signs is presented. The innovative technological core of the system is based on the use of a textile conformable sensing cloth, where conducting and piezoresistive materials are integrated in form of fibres and yarns, giving rise to fabric sensors, electrodes and connections. Electrocardiogram and impedance pneumography signals are acquired through the same textile electrodes, while to discriminate between abdominal and thoracic activity, two piezoresistive fabric sensors are placed below the lower end of the sternum and at the level of the navel for recording the thorax and the abdominal pattern of breathing. The use of impedance pneumography methodology reduces the artefacts due to the movement, phonation and rib cage expansions disjointed from respiratory mechanics. All the signals are acquired simultaneously allowing a comparative control of the cardiopulmonary activity and artefacts rejection.

12.
Stud Health Technol Inform ; 108: 209-13, 2004.
Article in English | MEDLINE | ID: mdl-15718648

ABSTRACT

Artificial sensory motor systems are now under development in a truly wearable form using an innovative technology based on electroactive polymers. The integration of electroactive polymeric materials into wearable garments endorses them with strain sensing and mechanical actuation properties. The methodology underlying the design of haptic garments has necessarily to rely on knowledge of biological perceptual and motor processes which is, however, scattered and fragmented. Notwithstanding, the combined use of new polymeric electroactive materials in the form of fibers and fabrics with emerging concepts of biomimetic nature in sensor data analysis, pseudomuscular actuator control and biomechanical design may not only provide new avenues toward the realization of truly wearable kinesthetic and haptic interfaces, but also clues and instruments to better comprehend human manipulative and gestual functions. In this talk the conception, early stage implementation and preliminary testing of a fabric-based wearable interface endowed with spatially redundant strain sensing and distributed actuation are illustrated with reference to a wearable upper limb artificial kinesthesia system, intended to be used in telerehabilitation of post stroke patient.


Subject(s)
Clothing , Kinesthesis , Monitoring, Ambulatory/instrumentation , Telemedicine/instrumentation , Humans , Monitoring, Ambulatory/methods , Polymers , Stroke/physiopathology , Stroke Rehabilitation , Telemedicine/methods , Textiles , Upper Extremity/physiopathology
13.
Stud Health Technol Inform ; 108: 266-70, 2004.
Article in English | MEDLINE | ID: mdl-15718655

ABSTRACT

Monitoring body kinematics and analyzing posture and gesture is an area of major importance in bioengineering and several other connected disciplines such as rehabilitation, sport medicine and ergonomics. Recent developments of new smart materials consent the realization of a new generation of garments with distributed sensors. What we present here is a sensing glove able to detect the posture and movements of the hand.


Subject(s)
Biosensing Techniques/methods , Clothing , Gestures , Hand/physiology , Monitoring, Ambulatory/instrumentation , Posture , Telemedicine , Biomechanical Phenomena/instrumentation , Humans , Monitoring, Ambulatory/methods , Silicone Elastomers , Textiles
14.
Stud Health Technol Inform ; 108: 324-9, 2004.
Article in English | MEDLINE | ID: mdl-15718662

ABSTRACT

In this paper several issues concerning the development of fibers endowed with electronic functions will be presented and discussed. In particular, issues concerning materials, structures, electronic models and the mechanical constraints due to textile technologies will be detailed. All these aspects have been studied in the framework of the project ARIANNE, funded by the European Community during the V Frame Programme.


Subject(s)
Biosensing Techniques/instrumentation , Computer Communication Networks/instrumentation , Electronics/instrumentation , Textiles , Biosensing Techniques/methods , Clothing , Feasibility Studies , Humans , Polymers , Transistors, Electronic
15.
Tissue Eng ; 8(6): 1089-98, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12542954

ABSTRACT

A technique for controlled deposition of biomaterials and cells in specific and complex architectures is described. It employs a highly accurate three-dimensional micropositioning system with a pressure-controlled syringe to deposit biopolymer structures with a lateral resolution of 5 microm. The pressure-activated microsyringe is equipped with a fine-bore exit needle and a wide variety of two- and three-dimensional patterns on which cells to be deposited can adhere. The system has been characterized in terms of deposition parameters such as applied pressure, motor speed, line width and height, and polymer viscosity, and a fluid dynamic model simulating the deposition process has been developed, allowing an accurate prediction of the topological characteristics of the polymer structures.


Subject(s)
Biocompatible Materials , Lactic Acid , Polyesters , Polymers , Syringes , Tissue Engineering
16.
Talanta ; 52(5): 921-30, 2000 Aug 16.
Article in English | MEDLINE | ID: mdl-18968053

ABSTRACT

The bioactivity of anti-human IgG Langmuir-Blodgett (LB) films, the non-specific adsorption of protein and the topography of anti-IgG LB films have been studied for application in immunosensors. The antibody (AB) LB films were horizontally deposited on glass and functionalized polymers, such as carboxy-poly(vinyl chloride) (PVC-COOH), chloropropyl and aminopropyl sol-gel. The LB films were characterized by means of ellipsometry, atomic force microscopy (AFM) and bicinchoninic acid (BCA) protein test. The interpretation of ellipsometric data was performed using a one-layer model. Non-specifically adsorbed protein was desorbed by washing the IgG film in 0.5 M NaCl, 2 M NaCl and 1% N-cetyl-N,N,N-trimethylammoniumbromide detergent solution resulting in a 50% reduction of the film thickness. The mean thickness of an anti-IgG film on glass measured by ellipsometry, PVC-COOH and aminopropyl sol-gel was 9+/-2, 11+/-1 and 23+/-8 nm, respectively. According to the BCA test 6-8 mug antibody (AB) per slide was bound to the functionalized polymers, but only 3 mug AB per slide was adsorbed on glass. The average distance of anti-IgG granules as indicated by AFM measurements on PVC-COOH, chloropropyl and aminopropyl sol-gel was 42+/-20, 34+/-3 and 23+/-4 nm. The average distance of granular AB structures on glass, however, was 150+/-50 nm.

17.
Science ; 284(5418): 1340-4, 1999 May 21.
Article in English | MEDLINE | ID: mdl-10334985

ABSTRACT

Electromechanical actuators based on sheets of single-walled carbon nanotubes were shown to generate higher stresses than natural muscle and higher strains than high-modulus ferroelectrics. Like natural muscles, the macroscopic actuators are assemblies of billions of individual nanoscale actuators. The actuation mechanism (quantum chemical-based expansion due to electrochemical double-layer charging) does not require ion intercalation, which limits the life and rate of faradaic conducting polymer actuators. Unlike conventional ferroelectric actuators, low operating voltages of a few volts generate large actuator strains. Predictions based on measurements suggest that actuators using optimized nanotube sheets may eventually provide substantially higher work densities per cycle than any previously known technology.

18.
J Biomater Sci Polym Ed ; 10(3): 295-304, 1999.
Article in English | MEDLINE | ID: mdl-10189098

ABSTRACT

The effect of endothelial cell adhesion on polyurethanes coated with Langmuir-Blodgett antibody films has been examined. The films were cross-linked with glutaraldehyde with the aim of providing a densely packed and covalently linked two-dimensional antibody network on the polyurethane surfaces. Our results demonstrate that although neither of the two polyurethanes examined were entirely suited to cellular adhesion, Langmuir-Blodgett antibody films, cross-linked with small concentrations of glutaraldehyde, are more suitable for endothelial cell adhesion than surfaces free of antibody.


Subject(s)
Antibodies, Monoclonal/chemistry , Biocompatible Materials/chemistry , Endothelium, Vascular/cytology , Polyurethanes/chemistry , Antibodies, Monoclonal/metabolism , Antigens, CD , Biocompatible Materials/metabolism , Biosensing Techniques , Cell Adhesion , Cross-Linking Reagents , Endoglin , Glutaral/chemistry , Humans , Materials Testing , Microscopy, Atomic Force , Receptors, Cell Surface , Surface Properties , Vascular Cell Adhesion Molecule-1/immunology
19.
Dermatol. peru ; 8(2): 93-7, jul.-dic. 1998. tab, graf
Article in Spanish | LILACS | ID: lil-289537

ABSTRACT

Se aporta los resultados de la I Jornada de Prevención, Diagnóstico y Tratamiento de Cáncer de Piel en una población predominante mestiza, de escasos recursos, y con intensa exposición al sol y al ambiente. Se detecta un sólo caso de cáncer de piel de tipo epitelioma basocelular en un paciente de tipo de piel II, por lo que se plantea la hipótesis de resistencia genética en la población mestiza. La revisión bibliográfica realizada es la primera actividad de prevención y detección de cáncer de piel en el mundo, que incluye el tratamiento quirúrgico y estudio histopatológico.


Subject(s)
Skin Neoplasms/diagnosis , Skin Neoplasms/prevention & control , Skin Neoplasms/therapy
20.
Article in English | MEDLINE | ID: mdl-18255952

ABSTRACT

Detection of incipient slippage is of great importance in robotics for the control of grasping and manipulation tasks. Together with fine-form reconstruction and primitive recognition, it has to be the main feature of an artificial tactile system. The system presented here is based on a neural network used to detect incipient slippage and on a skin-like sensor sensible to normal and shear stresses. Normal and shear stresses components inside the sensor are the input data of the neural net. An important feature of the system is that the a priori knowledge of the friction coefficient between the sensor and the object being manipulated is not needed. To validate the method we worked on both simulated and experimental data. In the first case, the finite element method is used to solve the direct problem of elastic contact in its full nonlinearity by resorting to the lowest number of approximations regarding the real problem. Simulation has shown that the network learns and is robust to noise. Then an experimental test was carried out. Experimental results show that, in a simple case, the method is able to detect the insipiency of slippage between an object and the sensor.

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