Catálogo de publicaciones - libros

In the recent past, it has been indicated that the liver consistency can be useful to estimate functional reserve for hepatectomy however, it is still unknown how the liver gets hardened when it becomes chronic hepatitis and cirrhosis. In this study, pathological model rats of liver cirrhosis and hepatitis were developed and the elasticity distribution over their sections were measured using Tactile Mapping system that was specifically designed to measure the two-dimensional elasticity distribution of very thin sliced tissues. The elasticity distribution images were then compared with the conventional azanstaining image to identify the tissues. Young’s modulus of both soft normal and hard fibrotic components exist in the sections were statistically compared and it was indicated that there was no significant difference in the elasticity of both components but the content ratio of harder fibrotic matrix was higher in the liver cirrhosis.

The purpose of this study was to determine the effects on lower extremities during muscle fatigue. The experimental trial of single-leg landing and jumping was conducted in a group of healthy male subjects. The experimental protocol included series of single-leg landings from elevated platform, single-leg jumps and fatiguing process that was kept at reasonable level, by asking each subject to make total of 60 two-legged squats. The results show that there was no significant change in overall shock attenuation prior and after the experiment. However the ankle work decreased, while the hip work increased. Even though the fatigue caused significant decrease in peak moments at the hip, knee and ankle joints, the significant increase in hip range of motion resulted in constant overall shock attenuation. The results suggest that the lower extremity is able to adapt to fatigue due to redistributing work to larger hip muscles.

The estimation of muscles and ligaments behavior can be useful in orthopaedic surgery or when a functional restoration may be reached by means of soft tissues surgery, i.e. in each case a different function is necessary to be planned for a muscle. Models of the skeletal muscle system were almost used to predict the rate of muscle-tendon lengthening during the most common tasks. In this work, a more general approach is proposed, in which individual anthropometry was considered through imaging processing, and joint kinematics captured in a movement analysis laboratory was used to animate a skeletal model, with the aim of simulating the effects of different surgical solutions on the muscle system functioning. To attain this result, the integration of different technologies, models and algorithms was required. After developing a model of the musculoskeletal and ligament system, the procedures for the pre-operative planning of both hip and knee joint replacement were simulated. A surgery planning tool based on the previously created model allowed the surgeon to plan an operation through a three-dimensional visualization of bones, by defining components’ sizes and improving their positioning by taking into account not only bone geometry but also the soft tissues spanning the articulations. Since the model is defined on a specific patient, it gives the possibility to increase model’s specificity with the aim of improving planning accuracy. The use of this planning tool can be useful both in pre-operative planning and during the surgical operation because the surgeon can develop skills in performing different operation’s steps. In this work, we considered two examples based on the model of muscles, bones and ligaments that was developed. The main steps of this procedure and the preliminary results are here presented pointing out the feasibility of the planning tool and of the model itself.

In order to increase the knowledge about heart and its physiology, a great number of experimental activities have being conducted. Part of such activities analyses single myocardial cells; usually, these processes present a lot of complications mainly concerning myocytes isolation, low reproducibility and high number of system related variables. Basing on these considerations the present work refers to the development of a numerical model of myocyte that permits to simulate its physiological contraction as well as pathological behaviours. The analysis of the single myocyte (the basic unit of cardiac tissue) is necessary to investigate heart as a single complex system in order to develop a numerical heart model able to simulate either the physiological and the pathological behaviour and thus overcome the experimental trials. The model enables the evaluation of contractility under three inotropic substances effect: angiotensin-II, endothelin-I and isoproterenol. It has been developed in three phases: an initial analysis of the behaviour of the sarcomere has been executed and a sarcomere model has been developed, such model permits to simulate both physiological activity of sarcomere and to analyze the inotropic effect of the three substances on it; finally a model of myocyte has been elaborated using both experimental data obtained from several trials previously defined and literature data; at the end the model has been validated both with literature results and with data obtained from subsequent experimental trials.

This work contributes to the methodology of an evaluation of elastic properties of cortical bones by ultrasonic wave inversion, whilst the bone is considered to be a linear elastic anisotropic continuum. Velocities of acoustic waves are used as an input data into inverse problem and they are experimentally detected by means of the ultrasonic based pulseecho immersion technique. The geometry of bone specimens is also implicated into algorithm by the model of wave propagation through curvilinear anisotropic sample based on the simplified ray method. The stability of resulting data is evaluated by the statistical method based on the Monte-Carlo simulation. The immersion method based on the wave inversion has shown to be a reliable tool for determination of some elastic constants only, the remaining coefficients need to be measured or improved by another experimental method. The ultrasonic contact pulse through transmission technique was rated as an acceptable experimental approach for this purposes. The RUS was found to be an unsuitable method for the measurement of the elastic coefficients of the cortical bone tissue.

This paper presents a musculotendon model for muscle force calculation based on Hill type model including viscoelastic properties of tendon. For describing the viscoelastic properties the Poynting-Thomson discrete model was used. The applied Hill type muscle model observes all active and passive properties of skeletal muscle. Differential equation which expresses musculotendon dynamics including constants which can be numerable from experimentally measured tendon tension, creep and relaxation data. This Model is suitable to use in forward dynamics problems and dynamic optimization approaches.

One of the main aims of the European Federation for Organisations of Medical Physics is to propose guidelines for education, training and accreditation programmes. This is achieved through the publication of Policy Statements and the organisation of education and training course, seminars and conferences. This is a continuous effort in an attempt to harmonise the education and training of the Medical Physicist across Europe. This paper presents an overview of the past, present and future efforts of EFOMP to achieve this aim.

In this paper we present the web-based elearning application on electrochemotherapy, an effective approach in local tumor treatment employing locally applied high-voltage electric pulses in combination with chemotherapeutic drugs. The antiumor treatment outcome is directly related to the electric field distribution in the target/tumor tissue. As the electric field distribution can not be displayed during the therapy we use numerical calculations in combination with web-based tools which allow visualizing and understanding the important parameters for effective electrochemotherapy.

Simulators were first used in aviation for flight training of pilots and for inter-staff communication. Regular training in the simulation centre is obligatory for all aircraft staff, whatever their rank or position. Simulation-based training has been introduced in nuclear power, space flight and petrochemical industries, particularly in the settings where there is a high probability of large-scale catastrophic events. The major advantages of learning skills on a simulator are: each procedure can be interrupted, improved and repeated until the required proficiency has been achieved, and no real harm is done when an eventual mistake –inadmissible in real clinical setting – is made on a mannequin. This learning modality is therefore less stressful for both the trainee and the teacher, and helps increase the trainee's self-confidence.

This paper briefly presents Biomedical Engineering (BME) in the virtual education. BME is a relatively new and highly multidisciplinary field of engineering. Due to its versatility and innovativeness, BME requires special learning and teaching methods. Virtual education is an emerging trend in the higher educational system. Technologies, learning theories, instructions, tutoring, and collaboration incorporated in the virtual education can lead to effective learning outcomes. European Virtual Campus for Biomedical Engineering (EVICAB) is the platform, where traditional biomedical education is transferred to the virtual.