3 resultados para Component specific damage index

em AMS Tesi di Laurea - Alm@DL - Università di Bologna


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Therapies for the treatment of prostate cancer show several limitations, especially when the cancer metastasizes or acquires resistance to treatment. In addition, most of the therapies currently used entails the occurrence of serious side effects. A different therapeutic approach, more selective and less invasive with respect either to radio or to chemotherapy, is represented by the photodynamic therapy (PDT). The PDT is a treatment that makes use of photosensitive drugs: these agents are pharmacologically inactive until they are irradiated with light at an appropriate wavelength and in the presence of oxygen. The drug, activated by light, forms singlet oxygen, a highly reactive chemical species directly responsible for DNA damage, thus of cell death. In this thesis we present two synthetic strategies for the preparation of two new tri-component derivatives for photodynamic therapy of advanced prostate cancer, namely DRPDT1 and DRPDT2. Both derivatives are formed by three basic elements covalently bounded to each other: a specific ligand with high affinity for the androgen receptor, a suitably chosen spacer molecule and a photoactivated molecule. In particular, DRPDT2 differs from DRPDT1 from the nature of the AR ligand. In fact, in the case of DRPDT2 we used a synthetically engineered androgen receptor ligand able to photo-react even in the absence of oxygen, by delivering NO radical. The presence of this additional pharmacophore, together with the porphyrin, may ensure an additive/synergistic effect to the photo-stimulated therapy, which than may act both in the presence of oxygen and in hypoxic conditions. This approach represents the first example of multimodal photodynamic therapy for prostate cancer.

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Damage tolerance analysis is a quite new methodology based on prescribed inspections. The load spectra used to derive results of these analysis strongly influence the final defined inspections programs that for this reason must be as much as possible representative of load acting on the considered structural component and at the same time, obtained reducing both cost and time. The principal purpose of our work is in improving the actual condition developing a complete numerical Damage Tolerance analysis, able to prescribe inspection programs on typical aircraft critical components, respecting DT regulations, starting from much more specific load spectrum then those actually used today. In particular, these more specific load spectrum to design against fatigue have been obtained through an appositively derived flight simulator developed in a Matlab/Simulink environment. This dynamic model has been designed so that it can be used to simulate typical missions performing manually (joystick inputs) or completely automatic (reference trajectory need to be provided) flights. Once these flights have been simulated, model’s outputs are used to generate load spectrum that are then processed to get information (peaks, valleys) to perform statistical and/or comparison consideration with other load spectrum. However, also much more useful information (loads amplitude) have been extracted from these generated load spectrum to perform the previously mentioned predictions (Rainflow counting method is applied for this purpose). The entire developed methodology works in a complete automatic way, so that, once some specified input parameters have been introduced and different typical flights have been simulated both, manually or automatically, it is able to relate the effects of these simulated flights with the reduction of residual strength of the considered component.

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The following thesis work focuses on the use and implementation of advanced models for measuring the resilience of water distribution networks. In particular, the functions implemented in GRA Tool, a software developed by the University of Exeter (UK), and the functions of the Toolkit of Epanet 2.2 were investigated. The study of the resilience and failure, obtained through GRA Tool and the development of the methodology based on the combined use of EPANET 2.2 and MATLAB software, was tested in a first phase, on a small-sized literature water distribution network, so that the variability of the results could be perceived more clearly and with greater immediacy, and then, on a more complex network, that of Modena. In the specific, it has been decided to go to recreate a mode of failure deferred in time, one proposed by the software GRA Tool, that is failure to the pipes, to make a comparison between the two methodologies. The analysis of hydraulic efficiency was conducted using a synthetic and global network performance index, i.e., Resilience index, introduced by Todini in the years 2000-2016. In fact, this index, being one of the parameters with which to evaluate the overall state of "hydraulic well-being" of a network, has the advantage of being able to act as a criterion for selecting any improvements to be made on the network itself. Furthermore, during these analyzes, was shown the analytical development undergone over time by the formula of the Resilience Index. The final intent of this thesis work was to understand by what means to improve the resilience of the system in question, as the introduction of the scenario linked to the rupture of the pipelines was designed to be able to identify the most problematic branches, i.e., those that in the event of a failure it would entail greater damage to the network, including lowering the Resilience Index.