9 research outputs found

    SIMULAZIONE DEL PROCESSO DI POLIMERIZZAZIONE IN AUTOCLAVE DI MATERIALI COMPOSITI E ANALISI DELLE NON CONFORMITA'

    Get PDF
    Lo studio effettuato permette di definire una metodologia per determinare il grado di polimerizzazione della resina di un componente in materiale composito prodotto in autoclave. Si analizzano gli effetti dovuti a malfunzionamenti o anomalie durante il processo di polimerizzazione e viene stabilita una procedura correttiva al fine di ottenere un componente polimerizzato in modo conforme. L’analisi numerica prevede l’interazione di due software per il calcolo agli elementi finiti. L’ambiente all’interno dell’autoclave viene simulato con un software per l’analisi fluidodinamica, il quale fornisce le condizioni al contorno necessarie per effettuare la simulazione agli elementi finiti della trasmissione del calore all’interno di un materiale in composito. In this thesis is defined a methodology able to determine the degree of cure of the resin of a composite element produced in autoclave. Effects due to anomalies in the right curing cycle are analyzed and a procedure is defined to fit these drawbacks. The numerical analysis provides the interaction of two finite element method (FEM) software. The fluid dynamics environment inside the autoclave is simulated using the software CD-adapco Star-CCM+® that gives for output the boundary conditions needed to make the heat transfer analysis through the composite on MSC Nastran®

    Advanced hepatocellular carcinoma and sorafenib: Diagnosis, indications, clinical and radiological follow-up

    Get PDF
    Advanced stage hepatocellular carcinoma (HCC) is a category of disease defined by radiological, clinical and hepatic function parameters, comprehending a wide range of patients with different general conditions. The main therapeutic option is represented by sorafenib treatment, a multi-kinase inhibitor with anti-proliferative and anti-angiogenic effect. Trans-arterial Radio Embolization also represents a promising new approach to intermediate/advanced HCC. Post-marketing clinical studies showed that only a portion of patients actually benefits from sorafenib treatment, and an even smaller percentage of patients treated shows partial/complete response on follow-up examinations, up against relevant costs and an incidence of drug related adverse effects. Although the treatment with sorafenib has shown a significant increase in mean overall survival in different studies, only a part of patients actually shows real benefits, while the incidence of drug related significant adverse effects and the economic costs are relatively high. Moreover, only a small percentage of patients also shows a response in terms of lesion dimensions reduction. Being able to properly differentiate patients who are responding to the therapy from non-responders as early as possible is then still difficult and could be a pivotal challenge for the future; in fact it could spare several patients a therapy often difficult to bear, directing them to other second line treatments (many of which are at the moment still under investigation). For this reason, some supplemental criteria to be added to the standard modified Response Evaluation Criteria in Solid Tumors evaluation are being searched for. In particular, finding some parameters (cellular density, perfusion grade and enhancement rate) able to predict the sensitivity of the lesions to anti-angiogenic agents could help in stratifying patients in terms of treatment responsiveness before the beginning of the therapy itself, or in the first weeks of sorafenib treatment. This would bring a strongly desirable help in clinical managements of these patients

    Comparing accuracy of tomosynthesis plus digital mammography or synthetic 2D mammography in breast cancer screening: baseline results of the MAITA RCT consortium

    No full text
    Aim: The analyses here reported aim to compare the screening performance of digital tomosynthesis (DBT) versus mammography (DM). Methods: MAITA is a consortium of four Italian trials, REtomo, Proteus, Impeto, and MAITA trial. The trials adopted a two-arm randomised design comparing DBT plus DM (REtomo and Proteus) or synthetic-2D (Impeto and MAITA trial) versus DM; multiple vendors were included. Women aged 45 to 69 years were individually randomised to one round of DBT or DM. Findings: From March 2014 to February 2022, 50,856 and 63,295 women were randomised to the DBT and DM arm, respectively. In the DBT arm, 6656 women were screened with DBT plus synthetic-2D. Recall was higher in the DBT arm (5·84% versus 4·96%), with differences between centres. With DBT, 0·8/1000 (95% CI 0·3 to 1·3) more women received surgical treatment for a benign lesion. The detection rate was 51% higher with DBT, ie. 2·6/1000 (95% CI 1·7 to 3·6) more cancers detected, with a similar relative increase for invasive cancers and ductal carcinoma in situ. The results were similar below and over the age of 50, at first and subsequent rounds, and with DBT plus DM and DBT plus synthetic-2D. No learning curve was appreciable. Detection of cancers >= 20 mm, with 2 or more positive lymph nodes, grade III, HER2-positive, or triple-negative was similar in the two arms. Interpretation: Results from MAITA confirm that DBT is superior to DM for the detection of cancers, with a possible increase in recall rate. DBT performance in screening should be assessed locally while waiting for long-term follow-up results on the impact of advanced cancer incidence
    corecore