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Muography applied to Archaeology: Search and 3D reconstruction of hidden cavities
No full textMuon radiography, also known as muography, is an imaging technique which exploits cosmic-ray muons to obtain an image of the internal structure of large volume bodies, such as volcanoes, pyramids or hills. It is in principle very similar to the common X-ray radiography, it indeed can provide the density distribution inside the object of interest measuring the absorbtion degree of muons after
crossing the body along different directions. Muography allows also to reveal the existance of unknown void regions, underground or inside large bodies; this feature
is of particular interest in the field of Archaeology giving the possibility to discover hidden cavities using a non-destructive technique. In this paper the application of muon radiography in the archaeological field will be presented, focusing particularly on the development of a novel approach to threedimensional imaging, where the
usual bidimensional muographies, taken from at least three different positions, are combined in order to localise cavities in space and reconstruct their shape
Teaching4Learning@UniPD: The experience of the Department of Physics and Astronomy
No full textTeaching4Learning (T4L) is a project of the University of Padua (UniPD) aimed at improving the quality of teaching in Higher Education by sustaining faculty professional development. The project features a series of residential
courses for faculty, with the goal of building a “Faculty Learning Community” in each department that shares experiences and good practices, and takes a reflective,
research-based approach to teaching. The Department of Physics and Astronomy joined the project in 2019 with the participation of 20 physics instructors in the firstlevel T4L course. In this contribution we describe the experience and its outputs, and we share some reflections and an outlook
The challenge of Quantum Manifesto for science education: Designing a teaching module on quantum computers for secondary school students
No full textAmong the key activities of Quantum Manifesto there is the formation of a new generation of quantum technology professionals in Europe through focused education at the intersection of different STEM and socio-economical disciplines and by strengthening public awareness of key ideas and capabilities. How can young people be guided to grasp the essence, potential and social implications of new quantum technologies? This paper presents how the research group in physics education of the University of Bologna is addressing the challenge launched by Quantum
Manifesto and is approaching the issue of designing teaching materials on quantum technologies aimed to enable secondary school students to grapple with the second
quantum revolution
RBE predictions by the BIANCA model for in vitro and in vivo irradiations in hadron therapy scenarios
No full textBIANCA is a two-parameter biophysical model that simulates chromosome aberrations and cell death induced by ionizing radiation, including ions of interest for hadron therapy. In this framework, the model parameters were tuned to
produce a radiobiological database describing the survival of V79 cells, chosen as a reference, after irradiation with different monochromatic ion beams. Afterwards, an
approach was developed to produce analogous databases for other cell lines, starting from their photon response; this approach allows performing full predictions for, in principle, any cell line. These databases can be read by a radiation transport code or a treatment planning system (TPS). Recently, BIANCA was interfaced to the FLUKA Monte Carlo code, and was applied to predict cell survival and RBE in typical hadron therapy scenarios. Very good agreement was found with in vitro data on the survival of CHO cells exposed along Spread Out Bragg Peaks of protons,
C- and He-ions. Furthermore, good agreement was obtained with in vivo RBE data on late effects in the rat spinal cord following irradiation with C-ions or protons.Finally, BIANCA was applied to two C-ion patient cases, showing predictions in line with other two models currently applied in clinics (LEM I and MKM). This work thus suggests that BIANCA can be used to predict RBE for hadron therap
Thermoluminescent dosimeters (TLDs-100) calibration for dose verification in photon and proton radiation therapy
No full textThermoluminescent dosimeters (TLDs) are practical, accurate, and precise tools for point dosimetry in medical physics applications. TLDs are nowadays extensively used to measure dose in conformal radiation therapy in order to
guarantee the safety of the treatment. Several national and international organizations recommend checking the effective dose delivered to an individual patient by means of in vivo dosimetry. Modern radiotherapy techniques employing both photon and ion beams exhibit excellent target conformation throught high steep-dose gradients between tumour and adjacent organs and tissues. In this context, catching potential dose errors and uncertainties in treatment delivering is the first step to ensure the optimization of the treatment plan. This study shows the results of the characterization of TLDs-100 at two Italian facilities devoted to advanced radiation treatments with photon and proton therapy. The individual sensitivity factor was determined, and the calibration curves were carried out in the dose range 0–20 Gy. By the analysis of the dose response curves, the linear region was identified under the dose level of 10 Gy. Characterization of the TLDs-100 has enabled their use for in vivo dosimetry especially in the dose range corresponding to the linear region of the dose response curves
Practical role of polymerization inhibitors in polymer gel dosimeters
No full textThe fundamental role of pre-treatment quality assurance in radiotherapy is to verify the radiation treatment with respect to the planned dose distribution by means of a devoted dosimeter. This step is necessary to achieve the
full clinical potential of the treatment by guaranteeing sparing of healthy tissues. In this study, the dose response of a modified version of the PAGAT polymer gel
dosimeter, a chemical dosimeter capable of direct 3D dose measurements, has been characterized. The physical response of the dosimeter is proportional to polymerization efficiency between its constituting monomers. The effect of several polymerization inhibitors in controlling the chemical response of the gel was investigated. The addition of these compounds allows a tailoring of the range of dose response of the gel to the dose range used in clinical practice. Obtained results from optical and magnetic resonance imaging analyses of irradiated gels indicate that an accurate control of inhibitor concentration can lead to a significant extension of the useful dose range, from approximately 4 Gy for the reference composition up to 40 Gy when inhibitors are added, with no significant detriment on fundamental dosimetric parameters such as accuracy, dose resolution and stability of the dose response
Natural radioactivity in soils and materials of the Campania region (Italy)
No full textThe results of radioactivity content of samples of different types of soils and building materials characteristic of the Campania volcanic region (South
Italy) have been reported and discussed. This characterization has been carried out by performing: i) γ-ray spectrometry measurement, using a hyperpure germanium
detector in very low background conditions, for the determination of the activity concentration of 226Ra, 232Th and 40K; ii) α-spectrometry of ionized descendants
of 222Rn, collected in an electrostatic cell, to measure the emanated fraction of this radioactive gas. Materials of different characteristic and origin have been studied.
Results prove the high radioactivity of the samples coming from this volcanic region, underlining the differences among their radioactivity content and their capacity to
generate radon
Musei in emergenza. Un sostegno forte e fragile per la comunità
Get PDFAt the time of collective disorientation due to the Coronavirus pandemic, museums have been called upon to strengthen their supporting role for communities, in compliance with containment measures.
Forced to close for many months, they have experienced a drastic reduction in revenues and a fragility of the work sector never seen before. Yet, they have been proactive in responding in their own way to the crisis, especially thanks to a very rapid and exponential increase in digital services.
During the lockdown, an overflowing use of social media was started, together with a proliferation of virtual visits to the now inaccessible collections, creative workshops for children and families, thematic lessons, podcasts, games and other initiatives suitable for creating entertainment, involvement and participation by the public.
This article aims to offer a wide reflection through a critical and reasoned overview of the international museum actions that have characterized the lockdown period
Boldo-Induced Hepatotoxicity: A Case of Unexplained Jaundice
Get PDFAn 87-year-old man was admitted with a 2-week history of asthenia, anorexia and jaundice. Blood tests showed increased serum liver enzymes. The aetiological study was inconclusive. The patient had a favourable clinical evolution during hospitalization with supportive care. His wife revealed that the patient had repeatedly consumed infusions of Peumus boldus (commonly known as boldo) leaves during the previous month. After common causes of hepatobiliary pathology were excluded, boldo-induced hepatotoxicity was considered probable. Cessation of its consumption led to complete clinical and laboratory recovery within a week
Radiotherapy-Associated Paraneoplastic Pemphigus and Its Complications in a Patient with Nasopharyngeal Carcinoma
Get PDFParaneoplastic pemphigus arising in association with non-haematological cancers is extremely rare, and there are no reported cases of a patient developing this in the setting of nasopharyngeal carcinoma and only 2 reported cases of patients developing this in response to radiotherapy. Here, we present the case of a patient who developed radiotherapy-associated paraneoplastic pemphigus in the setting of nasopharyngeal carcinoma and who then developed multiple complications