Assessment of natural radioactivity and radon release potential of silurian black shales

Many countries are developing a radon action plan to provide decision-makers with a reliable tool for reducing the harmful effects of radon exposure in dwellings and among the general public and, accordingly, to implement land development strategies. Mapping the geogenic radon release in different geological environments could assist in delineating areas that require priority monitoring and regulation, as well as applying radon reduction techniques in newly constructed buildings. In this paper, the activity concentration of 238U, 226Ra, 232Th and 40K and the exhalation rate of 222Rn have been estimated for the Silurian black shales of Villasalto, a district in the south-eastern Sardinia (Italy). The radioactivity of 226Ra, 232Th and 40K radionuclides was found relatively high (256.32 ± 87.00 Bq.kg−1), low (44.16 ± 9.47 Bq.kg−1) and moderate to high (856.28 ± 392.41 Bq.kg−1) respectively. The radon emanation coefficient (E) and the radon production rate (PRn) have been calculated based on the analysis of the radon growth model inside a sealed chamber. E was found to correlate well with the activity concentration of 226Ra, as well as with the grain size of the soil/rock samples under investigation. PRn was relatively high, ranging from 212.54 to 524.27 Bq.m−3.h−1. Furthermore, the mean value of the main radiation hazard indexes (i.e., the radium equivalent activity, the outdoor gamma-ray dose rate and the annual effective dose) were found to be 299.07 ± 138.62 Bq.kg−1, 169.97 ± 75.58 nGy h−1 and 0.21 ± 0.09 mSv.y−1 respectively

Notizia. Presentazione del volume di Monica Randaccio “Drama translation: theory and practice” (Trieste, Università degli Studi, 24 maggio 2023)

Vedere: http://hdl.handle.net/10077/3477

Traduzione aperta, quasi spalancata: tradurre Dario Fo

Il concetto di traduzione entra a far parte della storia del teatro molto tardi, poich\ue9 per lungo tempo si prefer\uec ricorrere alla tecnica dell\u2019imitazione e dell\u2019adattamento. A partire dal Settecento e in modo sempre pi\uf9 marcato sino ai nostri giorni, ci si \ue8 posti il problema del rapporto tra traduzione e messinscena, tra traduttore e regista, giungendo alla conclusione che tradurre per la scena richiede implicazioni e abilit\ue0 del tutto diverse da quelle impiegate nel tradurre un lavoro letterario. Al centro dei saggi che compongono questa pubblicazione vi \ue8 il teatro di Dario Fo, uno degli autori contemporanei pi\uf9 rappresentati e tradotti all\u2019estero. Al di l\ue0 delle questioni teoriche e critiche, il libro vuole essere un omaggio non solo a un grande drammaturgo ma a colui che in ogni sua opera ci ha indicato una via alla libert\ue0 di pensiero e al sapere, il cui vero senso risiede nel leggere, interpretare, verificare di persona. Perch\ue9, come ebbe a dire Fo, \u201cla conoscenza ti fa dubitare. Soprattutto del potere. Di ogni potere\u201d

Utilizzo di Image Plate per la dosimetria personale e ambientale

Purpose: A few years ago one of the largest manufacturers of photographic dosimeters has announced the discontinuation of production of this material, so the dosimetry services have had to find an alternative. We have begun to investigate the use of material based on photostimulable phosphors entirely similar to that used in computed radiography commonly referred to as Image Plate. In order to enable the use of new dosimeters phosphors we had to characterize the material, build the systems for reading and implementing the management software. After a few years of activity, we can say that the phosphor dosimeters combine the advantages of photographic dosimetry and TLD. Methods and materials: The use of materials similar to the image plate for the dosimetry of ionizing radiation has been proposed for several years and in all experiences was highlighted the extreme sensitivity on the one hand and on the other hand that the fading is the typical problem of these materials [1]. The material we used, mainly the IP Fuji model VI, presents a fading with two decay times of the signal, there is a very rapid reduction of the signal in the early hours, then the residual signal remains at nearly constant values for very long times, this allows the use in personal and environmental dosimetry that have cycle times of the order of one or more months. For the sequential read of hundreds of dosimeters has been designed and developed a scanner that can identify each dosimeter via a barcode and then capture an image that is stored in a file in DICOM format. The dose is evaluated on the basis of a calibration performed with radiation beams of variable energy between 40 and 1250 keV. The advantage of having images easily transferable in electronic form allows users to verify the actual irradiation conditions. Results: After a period of intense activity with the phosphor dosimeters we can say that there are numerous advantages compared to the photographic dosimetry and the TLD. The new method eliminates all chemical processes for the development of films that involve physical fatigue and problems for waste collection, you get a picture in digital format which allows a better evaluation of the dose and the ease in storing and transmitting data, finally, the sensitivity of the dosimeters phosphors is so high that can be used for measuring the environmental background. Conclusion: The availability of passive dosimeters similar to image plates has made significant improvements in radiation protection, has improved the sensitivity, linear response, the dynamic range but above all it is simple to archive the dosimeter image in the form of a file in DICOM format that can be easily transmitted through the network web. References: [1] D. Mouhssine, A. Nourreddine, A. Nachab, A. Pape, F. Fernandez : A new environmental dosimeter with imaging plates for the fast neutron monitoring, Nuclear Instruments and Methods in Physics Research B 227 (2005) 609–61

Detecting and evaluating minimal traces of radioisotopesin environment and foods

During the August 2012, 12 children from Japan have spent their holidays in Italy When they arrived we collected their urine and we found traces of Cs-137 and Cs-134. We again collected the urine before they leave Italy. In the first measurement we have found a clear sign of contamination by Cs-137 and Cs-134. The cesium is eliminated slowly. The daily amount of cesium excreted in urine is approximately 1% of the total cesium incorporated. The biological mean-life time of cesium is about 100 days. As a first ipothesys we can assume that the cesium contamination occurred during the first days after the accident in Fukushima. This assumption has been proved false by the final measurement after 25 days. At the end of the holidays we did a second measurement and we found a significant reduction in the activity not compatible with the hypothesis of acute contamination. Most likely the children have eaten contaminated food in the period prior to their departure from Japan, so we must assume a chronic contamination. The cesium in food is partly absorbed in the body and partly excreted daily in the urine. After a short time, an equilibrium condition is reached and the amount of cesium in the body remains constant, thus the amount of cesium which is excreted daily corresponds to the amount of cesium ingested daily with food. We measured the cesium excreted on the first day of arrival of the children, then we have an estimate of the amount of cesium taken daily with food. When the children started to eat uncontaminated food the equilibrium conditions were modified. In the urine there was only a fraction of cesium accumulated into the body. We know approximatively the fraction of cesium excreted daily (it about 1%) and we have measured it at the end of holidays, so we can calculate the total amount of cesium accumulated in to the boby. The first measurement can be used as an extimation of the cesium content in the food eaten daily. As a conclusion: there is still a contamination by Cs-137 and Cs-134 in environment and food in Japan, but the risk for the health is minimal in comparision with the most important natural radioisotope the Potassium 40. The european regulations fix a limit of 2 microgram per liter of Uranium in the mineral water used by new borns and children. This limit value (2 ppb) can be evaluated with a standard device like an ICP-MS. But often in our region the Uranium concentration is a thousandth of the limit value, just some ppt, so we need a more sensitive device: the Alfa spectroscopy. After a many-step chemical process the uranium has been fixed as a mono atomic layer on a steel plate. We use a Silicon Surface Barrier Detector to detect every single alfa particle and find the emitting radioisotope

A DVB-T framework for the remote monitoring of cardiopathic and diabetic patients

Tele-home care systems enable patients with chronic diseases to be remotely and constantly monitored by the healthcare staff reducing the need for frequent visits to the hospital. Besides the advantages for patients, this solution could also provide significant cost savings through the exploitation of low-cost equipment for simple physiological measurements to be performed at home, sending the recorded data to the healthier staff placed elsewhere. Tile aim of this work is the development of a low-cost tele-home care system based on the digital video broadcasting terrestrial (DVB-T) technology for the remote monitoring of cardiopathic and diabetic patients. Easy to use even by untrained or elderly people, such tele-home care system could represent the best solution in terms of simplicity, quality and costs