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The aim of this work was to develop a HIV-1 control strategy based on the nonlinear geometric control theory. Such a strategy was applied on a three variables deterministic model that describes the characteristic stages of the HIV-1 infection. The control design developed in this work allows the exact linearisation of the model. The results show that the nonlinear control developed is effective to...
Nowadays, circulatory support has become a common practice in medicine and a standard in the treatments of cardio vascular disease (CVD). A new pneumatic ventricular assist device (VAD) has been developed in Mexico City. This paper shows the first results of acute in-vivo trials, intended to verify the new system for providing physiological flows and pressures. Two VADs were implanted to as right...
Over the past ten years, we have tested and helped develop a multi-electrode array for chronic cortical recordings in behaving non-human primates. We have found that it is feasible to record from dozens of single units in the motor cortex for extended periods of time and that these signals can be decoded in a closed-loop, real-time system to generate goal-directed behavior of external devices. This...
High-level upper-limb amputations result in prostheses with many degrees-of-freedom to be controlled, with very few control signals. A novel method for the control of myoelectric upper limb prostheses has been developed. By transferring the residual nerves to spare muscles in or near the residual limb, additional myoelectric control signals are created that allow the simultaneous control of multiple...
This paper presents the identification and the study of the impact of a real-time MRI-based propulsion and tracking system constraints on the step response using a discrete PID controller. A simplified model for such a system accounts for these constraints such as the time delay, the sampling period, and the blood velocity. This application is intended for minimally invasive operations within the...
Remote controlled capsule (RCC) is a new method to realize non-invasive drug delivery to the selected sites of human gastro-intestinal (GI) tract. With RCC, human drug absorption (HDA) studies are taken easily to obtain data on the intestinal absorption of a drug in humans. In this paper, a new RCC system has been designed based on MEMS technology to provide for the delivery of a wide range of different...
Molecular techniques are transforming our understanding of cellular function and disease. However, accurate molecular analysis methods will be limited if the input DNA, RNA, or protein is not derived from pure population of cells or is contaminated by the wrong cells. Ultrasonic vibration microdissection provides the technology to procure pure population of targeted cells from tissue sections for...
In this paper, a novel, wearable cardiac monitor (hereafter called WHAM) is proposed which allows a continuous and real-time monitoring of user's cardiac conditions. The proposed device is composed of 3 main components: a disposable electrode, a controller, and personal gateway (e.g., cellular phone, PDA, and smart phone etc.). The ECG signal is recorded according to the surface Laplacian of the body...
Continuous flow blood pumps, such as axial flow and centrifugal pumps, have been gaining interest as circulatory devices for total artificial hearts (TAHs) and a biventricular assist device (BVAD) because of their smaller size and simpler structure compared to pulsatile pumps. However, continuous flow pumps are more prone to suction of the left ventricle than pulsatile pumps are. Sudden increases...
Sound modulated infrared (IR) light, as an alternative signal (and energy) transmission method, was evaluated for remote powering of a hearing implant via an implanted photodiode receiver. One human cadaveric temporal bone was used to test this concept by locating an IR source (LED) in the ear canal 4 mm away from the eardrum and a photodiode in the middle ear cavity. The photodiode output was directly...
The increasing number of physically challenged individuals has boosted the demand of powered wheelchairs. This paper is on the subject of a DSP (digital signal processors) based assistive system, which is associated with a two-level checking scheme. The assistive system takes on the M3S (multiple master multiple slave) regulation for the assurance of safety. The CAN (control area networks) embedded...
Impairment of hand function is prevalent among stroke survivors, motivating the search for effective rehabilitation therapy. Recent studies have suggested that for upper extremity functional recovery, repetitive training with virtual reality is helpful. Repetitive training can be facilitated with assistance from mechanical devices. Thus, we have developed a training environment that integrates augmented...
A measuring device for use in measuring calorie consumption includes a pulse input unit which detects a first heart rate of the user at a first point in an exercise period and a second heart rate of the user at a second point of the exercise period other than the first point, the pulse input unit not detecting a third heart rate between the first and second heart rates; and a controller which receives...
A new method for the propulsion of a spherical ferromagnetic device along a given path in a water filled phantom with no human interaction is presented using an 1.5 T magnetic resonance imaging (MRI) clinical system. A special real time loop is implemented and presented that feeds the scanner with the appropriate gradients amplitudes and directions based on a pre-determined path. This paper studies...
Recently, fully-implantable middle ear hearing devices (F-IMEHD) to enhance the hearing ability of auditory impaired persons have been developed in several countries. The implantable hearing device requires an external controller and a non-invasive power transmitter for recharging an internal battery of the device. This study shows the implementation of an inductively coupled control unit to be able...
Human fingers are easy to be injured. A CPM machine is a mechanism based on the rehabilitation theory of continuous passive motion (CPM). To develop a CPM machine for the clinic application in the rehabilitation of injured fingers is a significant task. Therefore, based on the theories of evidence based medicine (EBM) and CPM, we've developed a set of biomimetic mechanism after modeling the motions...
This paper describes a mechanical interface to use in conjunction with fMRI, in order to infer the brain mechanisms of human motor learning. Innovative mechanical concepts based on gravity and elastic forces were used to generate typical stable and unstable dynamic interactions at the hand during multijoint arm movements. Two designs were retained and implemented from MR compatible materials. The...
This paper presents a general method for hierarchical feedback control of redundant systems, and applies it to the problem of arm movement control. A high-level feedback controller, designed using optimal control techniques, operates on a simplified virtual plant. A low-level controller is responsible for performing a feedback transformation of the physical plant into the desired virtual plant. The...
Biofeedback and a variety of brain-computer-interface methods imply as very first stages the obtainment of control of selected signals e.g. the related generating psychophysiological processes. The basic mechanism in the learning phase is the operant conditioning, which represent a complex behavioral method consisting of several components. One of the most important components is the setting and adjustment...
A novel active surface Laplacian electroencephalogram (LEEG) sensor for the real-time mu rhythms detection has been developed in our study. Analog LEEG signals with high signal to noise ratio obtained directly by using the active sensor can reduce the duration and quantum error of digital signal processing and computation for the quick and precise control of brain-computer interface (BCI) systems...
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