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This paper introduces and evaluates BioLab, a tool for teaching biosignal processing. BioLab has been used in the biomedical engineering module that is given in the second semester of the fifth year of the electronic engineering degree at the University of Valencia, Spain. This module and its correspondent curricular pathway are also reviewed. BioLab allows the results obtained with digital processing techniques to be shown interactively in the theory classes, and it also provides support in laboratory sessions. The graphic interface of BioLab simplifies its learning and use and provides access to processing and visualization functions by means of menus. The tool is based on Matlab since the students have had previous experience in this environment. BioLab also supports diverse formats of data files, which facilitate access to real records and their conversion to usable formats. The modular structure of BioLab allows it to be easily extended to other educational materials that are related to signal processing and to research applications. An evaluation of BioLab has revealed that students found it useful for understanding the general concepts of digital processing and biosignal processing in particular. The students also found BioLab very easy to learn and use. Index Terms--Biomedical engineering (BME), digital signal processing (DSP), educational software, Matlab, project-based learning.

This paper presents a new approach to introducing adaptive filters based on the least-mean-square (LMS) algorithm and its variants in an undergraduate course on digital signal processing. Unlike other filters currently taught to undergraduate students, these filters are nonlinear and time variant. This proposal introduces adaptive filtering in the context of a linear time-invariant system using a real problem. In this way, introducing adaptive filters using concepts already familiar to the students motivates their interest through practical application. The key point for this simplification is that the input to the filter is constant so that the adaptive filter becomes linear. Therefore, a complete arsenal of mathematical tools, already known by the students, is available to analyze the performance of the filters and obtain the key parameters to adaptive filters, e.g., speed of convergence and stability. Several variants of the basic LMS algorithm are described the same way. Index Terms--Adaptive filters, algorithms, digital signal processing (DSP).

In this paper, we present four examples of effective implementation of neural systems in the daily clinical practice. There are two main goals in this work; the first one is to show that neural networks are especially well-suited tools for solving different kind of medical/pharmaceutical problems, given the complex input-output relationships and the few a priori knowledge about data distribution and variable relations. The second goal is to develop specific software applications, which enclose complex mathematical models, to clinicians; thus, the use of such models as decision support systems is facilitated. Four important pharmaceutical problems are considered in this study: identification of patients with potential risk of postchemotherapy emesis, classification of patients depending on their risk of digoxin intoxication, prediction of cyclosporine A through concentration and prediction of erythropoietin blood concentrations. The Multilayer Perceptron in classification problems and dynamic neural networks, such as the Elman recurrent neural network and the Finite Impulse Response neural network in prediction problems, have been used. Moreover, network ensembles of different kind of networks have been taken into account. Results show that neural networks are suitable tools for medical classification and prediction tasks, outperforming the mostly used methods in these problems (logistic regression and multivariate analysis). [ABSTRACT FROM AUTHOR]

Paresis of the oculomotor nerve is a very rare complication of an unrup-tured arteriosclerotic fusiform aneurysm of the basilar artery. A handful of cases are described in the world Literature. A fifty-four-year-old man with a history of hypertension and diabetes mellitus presented with painless partial oculomotor palsy of sudden onset. A cerebral angiogram demonstrated a tortuous fusiform deformity of the basilar artery and the origin of the posterior cerebral arteries, indicative of an arteriosclerotic aneurysmal dilation. A sudden onset of a pupil-sparing ophthalmoplegia is the typical history of a microvascular infarct of the third nerve, whereas pupillary sparing in aneurysmal oculomotor paresis is a very rare event. Special emphasis has been placed on the pupillary size as a guide for the indication of arteriography. The many exceptions to this rue suggest that cerebral arteriography may be indicated more often than generally believed. [ABSTRACT FROM AUTHOR]

Traumatic cerebral aneurysms (TCAs) are rare: few more than 100 cases are recorded in the world literature. TCAs are located predominantly in the supratentorial compartment and are classified as either "true" or "false". A true aneurysm is a dilation resulting from partial disruption of the arterial wall. A false aneurysm results from a full-thickness tear, with the scar from the brain tissue or an organized hematoma acting as the aneurysmal wall. The authors present a case of a false traumatic aneurysm of the pericallosal artery, which was discovered in a young patient fourteen months after a self-inflicted gunshot wound to his head. The aneurysm was an incidental finding on a CT scan performed for the investigation of his late posttraumatic seizures. Its presence was confirmed by angiography. The interval between the traumatic episode and the diagnosis of a TCA usually ranges from a few hours to a few weeks, for most are discovered by angiography performed in the acute or subacute stage of a head injury. The long interval between the injury and the diagnosis in our case is exceptional. A previous CT scan done four months after the injury did not reveal the aneurysm, which strongly suggests a protracted growth of the aneurysmal sac long after the trauma. [ABSTRACT FROM AUTHOR]

Contact thermography using liquid crystals provides a simple, inexpensive method of evaluating carotid disease. It does not duplicate information provided by other noninvasive methods, because, whereas Dopplers give an indication of flow and degree of stenosis in the artery, thermography measures the actual hypoperfusion as demonstrated by diminished temperature in areas of the forehead supplied by branches of the ophthalmic artery. A 74-year-old man presented with bilateral carotid distribution TIAs. Carotid Dopplers and angiography revealed 99% occlusion of both internal carotid arteries. Contact thermography showed diminished temperature in the right supraorbital artery territory. The patient subsequently underwent carotid endarterectomy. Following Induction of anesthesia but prior to carotid clamping, the patient became transiently hypotensive. Intraoperative EEG monitoring showed marked attenuation of the background rhythm on the right with preservation of background on the left. Normal rhythm was quickly restored with pharmacologic restoration of the blood pressure. This case illustrates the usefulness of thermography, which predicted the hemisphere in jeopardy when Dopplers and angiography showed equal bilateral disease. [ABSTRACT FROM AUTHOR]