Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947163
·
Publisher ↗
Recent literature support the idea of using an intense, task-oriented, stroke rehabilitation to promote motor learning and cerebral reorganization. Supporting a task-oriented, robot-assisted therapy approach requires bet...Recent literature support the idea of using an intense, task-oriented, stroke rehabilitation to promote motor learning and cerebral reorganization. Supporting a task-oriented, robot-assisted therapy approach requires better understanding of the components of real tasks and the limitations and benefits of current trajectory models. We set out to understand natural reach-to-grasp kinematics as it relates to various functional bilateral and unilateral tasks so as to better map this information to a robotic reach-to-grasp therapy systems. To do so, we investigated the influence of arm use and object functionality on four reaching kinematics in reach-to-grasp daily living tasks. We compared our results with the minimum jerk trajectory model used in robot-assisted therapy with the goal of understanding how best to support these real movements in a robotic environment. Eight neurologically intact, right handed subjects participated in the motion analysis study. They completed unilateral and bilateral reaching to objects in the same location with the same orientation, and with handles of the same size and shape. We discuss our results in terms of the minimum jerk model, which is typically used in robot-assisted trajectory planning. Our results showed significant differences in peak velocities, movement time and total displacement across tasks and across arm use conditions.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947162
·
Publisher ↗
The regulation of medical devices is well-established in industrialized countries, with increasing global standardization and harmonization. In developing and resource-poor countries, however, there is a much greater deg...The regulation of medical devices is well-established in industrialized countries, with increasing global standardization and harmonization. In developing and resource-poor countries, however, there is a much greater degree of variability and implementation. For such countries, this paper suggests a comprehensive and integrated regulatory framework approach using the South African health technology policy framework as a basis for comparison and benchmarking. It is hoped that this compact model, which covers a wide range of HTM-related aspects, will be useful to governments and their partners, amongst other role-players.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947161
·
Publisher ↗
The college diploma suffices for professional registration in Argentina and for the first time, Biomedical Engineering curricula have been included among those programs that need government and peers approval as their pr...The college diploma suffices for professional registration in Argentina and for the first time, Biomedical Engineering curricula have been included among those programs that need government and peers approval as their professional practice may affect citizen's health, safety or state. In this paper we present the standards that must be followed by BME programs and educational institutions in order to allow their graduates registration before professional boards.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947160
·
Publisher ↗
There are two activities for Japanese endoscopy information system. One is for a standard terminology (Minimal Standard Terminology: MST) for endoscopy reporting. Other is Integrating Healthcare Enterprise Japan (IHE-J)...There are two activities for Japanese endoscopy information system. One is for a standard terminology (Minimal Standard Terminology: MST) for endoscopy reporting. Other is Integrating Healthcare Enterprise Japan (IHE-J) for an integration of hospital information system. In IHE-J activity, the members revealed specificities of an endoscopy workflow by making a comparison with a radiology workflow. The authors will propose a scheme for systematic standardization based on our experiences in the standardization activities.
Gilja V, Linderman MD, Santhanam G
… +4 more, Afshar A, Ryu S, Meng TH, Shenoy KV
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947159
·
Publisher ↗
Continuous multiday broadband neural data provide a means for observing effects at fine timescales over long periods. In this paper we present analyses on such data sets to demonstrate neural correlates for physically ac...Continuous multiday broadband neural data provide a means for observing effects at fine timescales over long periods. In this paper we present analyses on such data sets to demonstrate neural correlates for physically active and inactive time periods, as defined by the response of a head-mounted accelerometer. During active periods, we found that 5-25 Hz local field potential (LFP) power was significantly reduced, firing rate variability increased, and firing rates have greater temporal correlation. Using a single threshold fit to LFP power, 93% of the 403 5 minute blocks tested were correctly classified as active or inactive (as labeled by thresholding each block's maximal accelerometer magnitude). These initial results motivate the use of such data sets for testing neural prosthetics systems and for finding the neural correlates of natural behaviors.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947158
·
Publisher ↗
This paper describes the design of a 21 degree-of-freedom, nine degree-of-actuation, gas-actuated arm prosthesis for transhumeral amputees. The arm incorporates a direct-drive elbow and three degree-of-freedom wrist, in...This paper describes the design of a 21 degree-of-freedom, nine degree-of-actuation, gas-actuated arm prosthesis for transhumeral amputees. The arm incorporates a direct-drive elbow and three degree-of-freedom wrist, in addition to a 17 degree-of-freedom underactuated hand effected by five actuators. The anthropomorphic device includes full position and force sensing capability for each actuated degree of freedom and integrates a monopropellant-powered gas generator to provide on-board power for untethered operation. Design considerations addressed in this paper include the sizing of pneumatic actuators based on the requisite output energy at each joint; the development of small low-power servovalves for use with hot/cold gases; the design of compact joints with integrated position sensing; and the packaging of the actuators, on-board power, and skeletal structure within the volumetric envelope of a normal human forearm and elbow. The resulting arm prototype approaches the dexterous manipulation capabilities of its anatomical counterpart while delivering approximately 50% of the force and power output of an average human arm.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947157
·
Publisher ↗
We envision cobotic infinitely-variable transmissions (IVTs) as an enabling technology for haptics and prosthetics that will allow for increases in the dynamic range of these devices while simultaneously permitting reduc...We envision cobotic infinitely-variable transmissions (IVTs) as an enabling technology for haptics and prosthetics that will allow for increases in the dynamic range of these devices while simultaneously permitting reductions in actuator size and power requirements. Use of cobotic IVTs eliminates the need to make compromises on output flow and effort, which are inherent to choosing a fixed transmission ratio drivetrain. The result is a mechanism with enhanced dynamic range that extends continuously from a completely clutched state to a highly backdrivable state. This high dynamic range allows cobotic devices to control impedance with a high level of fidelity. In this paper, we discuss these and other motivations for using parallel cobotic transmission architecture in prosthetic devices.
Flexman JA, Minoshima S, Kim Y
… +1 more, Cross DJ
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947156
·
Publisher ↗
Neural stem cell therapy for neurological pathologies, such as Alzheimer's and Parkinson's disease, may delay the onset of symptoms, replace damaged neurons and/or support the survival of endogenous cells. Magnetic reson...Neural stem cell therapy for neurological pathologies, such as Alzheimer's and Parkinson's disease, may delay the onset of symptoms, replace damaged neurons and/or support the survival of endogenous cells. Magnetic resonance imaging (MRI) can be used to track magnetically labeled cells in vivo to observe migration. Prior to transplantation, labeled cells must be characterized to show that they retain their intrinsic properties, such as cell proliferation into neurospheres in a supplemented environment. In vivo images must also be correlated to sensitive, histological markers. In this study, we show that fetus-derived neural stem cells can be co-labeled with superparamagnetic iron oxide and PKH26, a fluorescent dye. Labeled cells retain the ability to proliferate into neurospheres in culture, but labeling prevents neurospheres from merging in a non-adherent culture environment. After labeled NSCs were transplantation into the rat brain, their location and subsequent migration along the corpus callosum was detected using MRI. This study demonstrates an imaging paradigm with which to develop an in vivo assay for quantitatively evaluating fetal neural stem cell migration.
Alacam B, Yazici B, Serdaroglu A
… +3 more, Intes X, Chance B, Nioka S
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947155
·
Publisher ↗
In this work, we propose a method to reconstruct spatially resolved pharmacokinetic rate images of fluorescence agents directly from the boundary photon flux measurements. We use a compartmental modeling scheme to model...In this work, we propose a method to reconstruct spatially resolved pharmacokinetic rate images of fluorescence agents directly from the boundary photon flux measurements. We use a compartmental modeling scheme to model the pharmacokinetics of fluorescence agents. We coupled this model with the fluorescence diffuse optical tomography (FDOT) forward model to form a state space model which is then iteratively solved by extended Kalman filtering (EKF) algorithm. As an example, we used a two-compartment model for indocyanine green (ICG) pharmacokinetics. To validate the proposed method, we tested our approach using a simulation study. Reconstructed pharmacokinetic rate images with correct localization of heterogeneities and high reconstruction accuracy show that the proposed algorithm can be used for tumor detection, tumor diagnosis, drug delivery and feasibility studies.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947154
·
Publisher ↗
We present a silicon-based implantable drug delivery system (IDDS) for the administration of compounds in vivo. The implanted device contains the drug-filled silicon microchip, control circuitry, telemetry capability, an...We present a silicon-based implantable drug delivery system (IDDS) for the administration of compounds in vivo. The implanted device contains the drug-filled silicon microchip, control circuitry, telemetry capability, and a battery. At the heart of the IDDS is the drug-containing microchip, a MEMS (MicroElectroMechanical Systems)-based device. A process was developed for the fabrication of the silicon chip. MicroCHIPS' drug release technology has been successfully demonstrated in vitro and in vivo using the therapeutic peptide leuprolide as a model compound.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947153
·
Publisher ↗
Electric field mediated drug and gene delivery is a novel method that uses pulsed electric fields to improve permeability of cell membranes and therefore desired agent uptake by tissues. In this paper, we describe the mo...Electric field mediated drug and gene delivery is a novel method that uses pulsed electric fields to improve permeability of cell membranes and therefore desired agent uptake by tissues. In this paper, we describe the modeling and experimental proof of concept of a method to direct electric fields to subsequently focus drug or gene uptake at a desired site. The in vitro experimental results presented are consistent with simulation models and could be scaled into different in vivo applications that can concentrate the effects of electroporation and overcome several problems related to localized effects near the electrodes.
Rajagiri A, Diong B, Goldman M
… +1 more, Nazeran H
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947152
·
Publisher ↗
This paper describes the estimation of the parameter values for the recently introduced augmented RIC respiratory system model from impulse oscillometry data obtained from both asthmatic and normal children. An analysis...This paper describes the estimation of the parameter values for the recently introduced augmented RIC respiratory system model from impulse oscillometry data obtained from both asthmatic and normal children. An analysis of these values has indicated that one of the capacitance parameters of the model provides good discrimination between these two groups of children; moreover, this finding corresponds well with current medical understanding of the pathology of asthma.
Giraldo B, Garde A, Arizmendi C
… +4 more, Jańe R, Benito S, Diaz I, Ballesteros D
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947151
·
Publisher ↗
One of the most frequent reasons for instituting mechanical ventilation is to decrease patient's work of breathing. Many attempts have been made to increase the effectiveness of the evaluation of the respiratory pattern...One of the most frequent reasons for instituting mechanical ventilation is to decrease patient's work of breathing. Many attempts have been made to increase the effectiveness of the evaluation of the respiratory pattern with the analysis of the respiratory signals. This work proposes a method for the study of the differences in respiratory pattern variability in patients on weaning trials. The proposed method is based on a support vector machine using 35 features extracted from the respiratory flow signal. In this paper, a group of 146 patients with mechanical ventilation were studied: group S of 79 patients with successful weaning trials and group F of 67 patients that failed to maintain spontaneous breathing and were reconnected. Applying a feature selection procedure based on the use of the support vector machine with a leave-one-out cross-validation, it was obtained 86.67% of well classified patients on group S and 73.34% on group F, using only 8 of the 35 features. Therefore, support vector machine can be a classification method of the respiratory pattern variability useful in the study of patients on weaning trials.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947150
·
Publisher ↗
A noncontact method for measuring saccadic eye movement with two high-speed cameras is proposed. The method is based on image processing for acquiring the center gravity of one pupil of the subject and also on stereo pho...A noncontact method for measuring saccadic eye movement with two high-speed cameras is proposed. The method is based on image processing for acquiring the center gravity of one pupil of the subject and also on stereo photogrammetry for estimating three-dimensional coordinate of the pupil. The proposed method was examined through experiments using a imitated eye ball and using a real human subject. The results showed a possibility of the method for the measurement. Since dynamic characteristics of the saccadic eye movement is reported as a promising index for monitoring human vigilance level according to the author's previous research works, this method can be utilized for accident prevention system in the future. However, there is still room for improvement in measuring accuracy and stability to the body motion in terms of its practical use.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947149
·
Publisher ↗
Measurement of oxygen saturation levels in blood is a vital activity during most medical treatments. A pulse oximeter is a device most commonly used to perform this measurement. It provides convenient, non-invasive and c...Measurement of oxygen saturation levels in blood is a vital activity during most medical treatments. A pulse oximeter is a device most commonly used to perform this measurement. It provides convenient, non-invasive and continuous monitoring of oxygen levels in a human body. However, it is often a tedious task to select the appropriate hardware and software components to manufacture a pulse oximeter that gives accurate results. This paper describes a student project, which had the goals to expose the student to this important technique of applying rapid prototyping methods to the design of a state of the art pulse oximeter.
Fury W, Batliwalla F, Gregersen PK
… +1 more, Li W
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947148
·
Publisher ↗
When the same set of genes appear in two top ranking gene lists in two different studies, it is often of interest to estimate the probability for this being a chance event. This overlapping probability is well known to f...When the same set of genes appear in two top ranking gene lists in two different studies, it is often of interest to estimate the probability for this being a chance event. This overlapping probability is well known to follow the hypergeometric distribution. Usually, the lengths of top-ranking gene lists are assumed to be fixed, by using a pre-set criterion on, e.g., p-value for the t-test. We investigate how overlapping probability changes with the gene selection criterion, or simply, with the length of the top-ranking gene lists. It is concluded that overlapping probability is indeed a function of the gene list length, and its statistical significance should be quoted in the context of gene selection criterion.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947147
·
Publisher ↗
Cluster analysis has become a standard part of gene expression analysis. In this paper, we propose a novel semi-supervised approach that offers the same flexibility as that of a hierarchical clustering. Yet it utilizes,...Cluster analysis has become a standard part of gene expression analysis. In this paper, we propose a novel semi-supervised approach that offers the same flexibility as that of a hierarchical clustering. Yet it utilizes, along with the experimental gene expression data, common biological information about different genes that is being complied at various public, Web accessible databases. We argue that such an approach is inherently superior than the standard unsupervised approach of grouping genes based on expression data alone. It is shown that our biologically supervised methods produce better clustering results than the corresponding unsupervised methods as judged by the distance from the model temporal profiles. R-codes of the clustering algorithm are available from the authors upon request.
Castellanos G, Delgado E, Daza G
… +2 more, Sánchez LG, Suárez JF
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947146
·
Publisher ↗
Heuristical algorithms can reduce the computational complexity. Such methods require of some stopping criteria (cost function). Some of these cost functions are based on statistics like univariate and multivariate method...Heuristical algorithms can reduce the computational complexity. Such methods require of some stopping criteria (cost function). Some of these cost functions are based on statistics like univariate and multivariate methods of analysis. Dimensional reduction techniques such as principal component analysis (PCA) allow to find a lower dimension transformed space based on data variance, but this procedure does not take into account information about classes separability, the direction of maximum variance does not necessarily correspond to the direction of maximum separability. In this work, we propose a feature selection algorithm with heuristic search that uses multivariate analysis of variance (MANOVA) as the cost function. This technique is put to test by classifying hypernasal from normal voices of CLP (Cleft Lip and/or Palate) patients. The classification performance, computational time and reduction ratio are also considered by the comparison with an alternate feature selection method founded on unfolding the multivariate analysis into univariate and bivariate analysis.
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947145
·
Publisher ↗
We present here results from a preliminary trial of brain activation data collection by near infrared spectroscopy (NIRS). Light in the NIR region was incident upon the human motor cortex in anticipation of observing a d...We present here results from a preliminary trial of brain activation data collection by near infrared spectroscopy (NIRS). Light in the NIR region was incident upon the human motor cortex in anticipation of observing a detectable change during periods of motor activation with respect to periods of rest. Frequency domain near infrared spectroscopy (NIRS) was used to obtain the amplitude (AC) and intensity (DC) of the NIR signal after it passed through the brain tissue. Analysis of the DC component indicates that the absorptive properties of the tissue are altered during periods of activation. Spectral estimation reveals some frequency components in both amplitude and intensity signals that may serve to discriminate between the periods of activation and the periods of rest. These characteristic differences may be harnessed to control a brain computer interface (BCI).
Aziz JN, Karakiewicz R, Genov R
… +3 more, Bardakjian BL, Derchansky M, Carlen PL
Conf Proc IEEE Eng Med Biol Soc
· 2006 · PMID 17947144
·
Publisher ↗
We present an architecture of an epileptic seizure prediction system suitable for an implantable implementation. The microsystem comprises a neural interface, a spectral analysis processor and an artificial neural networ...We present an architecture of an epileptic seizure prediction system suitable for an implantable implementation. The microsystem comprises a neural interface, a spectral analysis processor and an artificial neural network (ANN). The neural interface and the spectral analysis processor have been prototyped in a 0.35 microm CMOS technology with experimental results are presented. The wavelet-based artificial neural network predicts the onsets of seizure up to two minutes before their occurrence in an in-vitro epilepsy model using a mouse hippocampal brain slice with recurrent spontaneous seizures.