Various in vivo experimental works carried out on different animals and organs have shown that it is possible to reduce the damage caused to healthy tissue still preserving the therapeutic efficacy on the tumor tissue, by drastically reducing the total time of dose delivery (<200 ms). This effect, called the FLASH effect, immediately attracted considerable attention within the radiotherapy community, due to the possibility of widening the therapeutic window and treating effectively tumors which appear radioresistant to conventional techniques. Despite the experimental evidence, the radiobiological mechanisms underlying the FLASH effect and the beam parameters contributing to its optimization are not yet known in details. In order to fully understand the FLASH effect, it might be worthy to investigate some alternatives which can further improve the tools adopted so far, in terms of both linac technology and dosimetric systems. This work investigates the problems and solutions concerning the realization of an electron accelerator dedicated to FLASH therapy and optimized for in vivo experiments. Moreover, the work discusses the saturation problems of the most common radiotherapy dosimeters when used in the very high dose-per-pulse FLASH conditions and provides some preliminary experimental data on their behavior.

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This paper proposes a mathematical programming approach for empty container management. Since directional imbalances in trade activities result in a surplus or shortage of empty containers in ports and depots, their management can be thought of as a min cost flow problem whose arcs represent services routes, inventory links and decisions concerning the time and place to lease containers from external sources. We adopt an hourly time-step in a dynamic network and, although this time-period generates large-size instances, the two implemented algorithms show a good computational efficiency. A possible case study of the Mediterranean basin is proposed and results are presented with a graphical representation, providing a useful support to decision-makers in the field. Maritime Economics & Logistics (2005) 7, 199–222. doi:10.1057/palgrave.mel.9100136

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