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Modelling of the sound transmission process from the external ear canal through the middle ear structures to the cochlea is often performed using the finite element method. This requires knowledge of the geometry of the object being modelled. The paper shows the results of reconstruction of the 3D geometry of the ossicular chain. The micro-CT images of a cadaver's temporal bone were used to carry...
The effect of sputtering with a conductor of the semi-permeable membranes surface on SEM pictures obtained is presented. On the example of photomicrographs of several different types of semi-permeable membranes, changes in the appearance of various membrane surfaces, uncovered and sputtered with thicker and thicker layers of the conductor are presented. It has been shown, how essential differences...
Though potentially relevant for monitoring of acute stroke, even specialized stroke units do not provide continuous methods to determine cerebral perfusion at the bedside. We present patient measurements on cerebral perfusion in ischemic stroke applying optical bolus tracking. To this end, our portable time-domain near-infrared reflectometer has been optimized and technically approved for clinical...
The application of spectroscopic study, microscopic and AFM imaging for examination of fiberoptic applicators is presented. The potential carriers of photoactive agents for photodynamic medicine in form of sol-gel coatings of fiberoptic applicators, are proposed. Optical and morphological properties of the proposed sol-gel coatings doped with photosensitizer Photolon, are characterized. The influence...
Laser Doppler flowmetry (LDF) signals - that reflect the peripheral cardiovascular system - are now widespread in blood microcirculation research. Over the last few years, the central cardiovascular system has been the subject of many fractal and multifractal works. However, only very few multifractal studies of LDF signals have been published. Such multifractal analyses have shown that LDF data can...
Here we review the state of the art using saccadic eye movements as windows to the function of the normal brain and of the abnormal brain plagued by disease or trauma. By combining sophisticated behavioral paradigms with rigorous mathematical analysis and the latest imaging techniques one can use saccades as biomarkers of the highest level decision making to the lowest level basic machinery that generates...
The paper presents a method for the preparation of sulfonated polysulfone in order to receive a matrix to immobilisation of biomolecules. Optimum conditions of the synthesis are described. The phase inversion method was used to prepare a sulfonated polysulfone membrane and then urease was immobilized on the surface of the prepared matrix. Comparison of activity of native urease and the immobilized...
Standard multivariate statistical methods in medical applications are too sensitive to the assumption of multivariate normality and the presence of outliers in the data. This paper is devoted to robust statistical methods. In the context of medical image analysis they allow to solve the tasks of face detection and face recognition in a database of images. The results of the robust approaches in image...
Measuring saccadic reaction time distributions is an increasingly popular technique, making it possible to obtain a large amount of data non-invasively in a short period of time. Such distributions can often be encapsulated with just two parameters, representing the mean and variance of the rate of rise in the LATER model. For many purposes, both scientific and clinical, this is enough. But for normal...
To reveal some functional constraints of the saccade inhibitory neuronal circuits, we investigated the influence of response monitoring in human. The subjects were instructed to perform a stop signal task in which the probability of stop trial occurrence was manipulated. The purpose of the work was to evaluate the time course necessary to adapt the behavior to changes in the occurrence of stop signal...
Multiple classifier fusion may generate more accurate classification than each of the constituent classifiers. The aim was to examine the ensemble performance by the comparison of boosting, bagging and fixed fusion methods for aiding diagnosis. Real-life medical data set for thyroid diseases recognition was applied. Different fixed combined classifiers (mean, average, product, minimum, maximum, and...
The results of the investigatigation of afterhyperpolarization (AHP) duration in normal aging and selected neuromuscular disorders are presented. This investigation yielded unexpected results: the AHP shortening in myogenic disease (DMD) and no significant difference from control values in neurogenic disease (ALS). However, introduction of age factor revealed novel aspects of the human ALS, which...
One of possible ways to speed-up the prosaccadic latency examination is applying the target walk paradigm. The authors describe the physiological phenomena involved in carrying such paradigms, which may affect latency time and which should be balanced in this kind of task. Thirteen subjects were examined applying the newly designed target-walk paradigm and for comparison the standard prosaccade task...
Surface EMG comprises a variety of widely applied experimental tools in basic neuroscience, biomechanics and exercise physiology, but also in applied disciplines like clinical neurophysiology, ergonomics and sports sciences. To increase the usefulness of surface EMG, we contributed to the introduction and application of a spatiotemporal variant of the usual single channel surface EMG techniques, called...
This work investigated an effective method of isolation and culture of human autologous chondrocytes placed on a polysulphonic membrane. The cartilage was taken from the hip joint of 78 years old woman who underwent total hip ar throplasty due to idiopatic arthrosis and from the knee of 46 years old man with cartilage lesion from non-weight bear area. The cells were released from the matrix in the...
Regression models of censored survival data are often required to handle the cases, where information on the dependent (response) variable is only available as intervals, within which the actual values are located. We report on implementation and some preliminary tests of a new general method for regression with an interval-censored response variable. This method is based on minimization of a convex...
During natural contractions motor units (MUs) are activated by variable frequency discharge patterns of motoneurones. The aim of this review was (1) to discuss differences between tetanic contractions developed at constant and random frequencies of pulses; (2) to show results of mathematical decomposition of these tetani into series of twitch-shaped responses to individual pulses; (3) to indicate...
A hybrid (Hydro-numerical) model of blood circulation developed at the Institute of Biocybernetics and Biomedical Engineering (IBIB) of the Polish Academy of Sciences (PAN) -Warsaw, Poland, in co-operation with the Institute of Clinical Physiology (IFC) of the National Council of Research (CNR) - Rome, Italy, is a basic model of this type solutions commonly accepted by the researchers. It is able...
The aim of the present study was to verify a system for continuous monitoring of feet temperature. The temperature measurement system developed in cooperation of the Center for Biomedical Technology (Krems, Austria) and Digilog Inc. (Perg, Austria) company was used for monitoring of the skin temperature on foot. The temperature monitoring devices are wirelessly controlled and they could be encapsulated...
This article summarizes the pathogenic mechanisms known to be responsible for sporadic amyotrophic lateral sclerosis, such as excitoxicity, endoplasmic reticulum stress, oxidative stress, proteins damage, inflammation, genes abnormalities and neuronal death; some clinical features of the disorder are discussed as well. Finally, it puts forward the hypothesis that astrocytes, rather than the motor...
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