Biomedical Engineering

Introduction and generalities' The Bohr atom. atomic levels. The nucleus. nuclear levels. Radiation α, β, γ. Radioactive decay and half-life. Cross section and probability 'of interaction 2 Photons Photoelectric effect. Planck constant and the concept of the photon. Thomson Scattering: polarized and unpolarized cross section. Rayleigh Scattering. Compton Effect. Pairs production and electromagnetic showers. Attenuation and absorption of X-rays 3 Charged particles Energy loss of charged particles. Range. Fluctuation of energy loss. Bremsstrahlung. Angular distribution. 4 Neutrons Scattering of neutrons. Moderation of neutrons 5 Radiation detectors Ionization in gases. ionization in gas detectors. Scintillation. Scintillation counters. photographic film. Counters Thermoluminescence 6 Dosimetry Units and dosimetric quantities. Fluence. Exposure. Kerma. Dose. Measurements of dose and exposure. Build-up. Radiation shielding. Principles of radiation protection and dose limits. 7 Biological effects of radiation. Biological effects. Sources of radiation data. Radiobiology. Dose-response relationship: X-rays, charged radiation, neutrons. Cell survival. Relative Biological Effectiveness 9 diagnostic and therapeutic techniques The Single Photon Emission Computed Tomography. The Positron Emission Tomography. Radiotherapy. Particle therapy

Knowledge of electromagnetism and electromagnetic fields - elements of probability and statistics

James Turner: "Atoms, radiation and radioprotection"

Attendance in the classroom for theoretical lessons three times a week and once a week in the laboratory for experiments

The oral test concerns the evaluation of knowledge on medical techniques using radiation. In particular, the basics of nuclear physics applied to medicine and the fundamentals of radiation protection will be the subject of examination. The knowledge of nuclear imaging techniques will be evaluated with particular regard to the technological design of SPECT and PET machines. Knowledge of the application of radiation physics to radiotherapy of solid tumors will also be the subject of examination.

Theoretical lessons are held in person. The laboratory experiences (one a week) are held in presence

Elements of probability and statistics applied to counting techniques. Features (trend, mean, variance, use) of probability distributions: binomial, Poisson, exponential, Gaussian, chi2 [is not required to know the derivation of the distributions] Chi2 test: study of poissonian distributions. Description of the measuring system used in the laboratory: Inorganic scintillators, in particular CsI (Tl) and their characteristics: luminous efficiency, emission spectrum, temporal characteristics. Collection of light. Photomultiplier: in particular: the characteristics of the photocathode, relationship gain-HV, simplified diagram of the voltage divider used. Discrimination of signals and training time. Dead time: its definition approximate (linear) and exponential. Determination of the frequency of counts in presence of dead time. Interaction with the scintillator of photons produced in the decay chains of Na22 Cs137 Co60.Effects of resolution on the amplitude spectrum measured in the laboratory. Solid angle and 1/r2 trend. Activity estimation of the radioactive sources used. Attenuation and absorption of gamma radiation in Al, Fe, Cu, Zn and brass. Relationship with the detection efficiency in the CsI (Tl). Energy calibration and energy resolution of the counter

The laboratory module does not have any specific pre-requisite as the student will be introduced, along the course, to all the needed technological knowledge to carry out the experiments and the theory elements that are needed for data processing and the relative statistical analysis will be provided as well to ensure that the student is capable to understand the outcome of the experiments. The student can be helped in his study by fundamental notions provided in Physics 1 and Physics 2 classes, by the fundamental notions of statistics (definition and propagation of uncertainties, Poisson and Gaussian distributions,..) and the use of software tools like matlab or xcel.

The adopted textbook are presented along the course development and are those focused on the different course core items. Particular attention will be made underlining the experimental part of what is observed and done in the laboratory experimental part.

The course consists of two parts: the first part concerns the 4-5 laboratory experiences that take place in the Didactic Laboratory of Physics (LaDiFi) in via del Castro Laurenziano (Laboratory B). Each student is required to attend the laboratory experiences, carry out the measurements, and keep their own laboratory diary and prepare a laboratory notebook for discussion during the exam. In addition to these 4-5 mornings (9:00 - 13:00, each single experience lasts 4 hours), there are 8-9 2-hour frontal lessons in which the experiences are presented, the theoretical elements discussed and the measurement tools, statistical analysis and what is expected to be measured from a theoretical point of view is reviewed.

The attendance of the laboratory experiences is compulsory, that of the lessons is not. However, it is strongly recommended that students attend in person in order to facilitate their learning and avoid problems during the exam.

The assessment of knowledge will take place in an oral exam in which the student will have to illustrate the content and development of one of the experiences made in the laboratory, demonstrate knowledge of the details of the experimental apparatus used and the methods of data analysis it has implemented and, finally, he will have to answer a question related to the theory module in which the detail of the decay of the radioactive source used in the laboratory was presented, and the mechanism for measuring the decay products was discussed as well.