Learning and testing the bounded retransmission protocol

Abstract Using a well-known industrial case study from the verification literature, the bounded retransmission protocol, we show how active learning can be used to establish the correctness of protocol implementation I relative to a given reference implementation R. Using active learning, we learn a model M R of reference implementation R, which serves as input for a model based testing tool that checks conformance of implementation I to M R . In addition, we also explore an alternative approach in which we learn a model M I of implementation I, which is compared to model M R using an equivalence checker. Our work uses a unique combination of software tools for model construction (Uppaal), active learning (LearnLib, Tomte), model-based testing (JTorX, TorXakis) and verification (CADP, MRMC). We show how these tools can be used for learning these models, analyzing the obtained results, and improving the learning performance

Cytoreductive surgery and radioimmunotherapy to treat peritoneal carcinomatosis of colorectal cancer : investigations towards improvement of outcome and morbidity

Contains fulltext : 65647_cytosuanr.pdf (publisher's version ) (Open Access)The clinical treatment of first choice for peritoneal carcinomatosis of colorectal cancer is HIPEC. In order to improve outcome and morbidity, new treatment strategies have been developed, one of which is radioimmunotherapy. The results of clinical trials investigating regionally administered radioimmunotherapy are described in Chapter 2. In Chapter 3, it was investigated whether survival after intraperitoneally administered RIT can be enhanced by altering the time interval between the surgical procedure and the intraperitoneal administration of RIT. We concluded that the efficacy of adjuvant RIT after cytoreductive surgery (CS) for the treatment of experimental PC of colonic origin decreases when the administration of the radiolabeled MAbs is postponed. In Chapter 4, the concomitant administration of rtPA or wholebody hyperthermia after CS and RIT was investigated. We concluded that both applications did not significantly potentiate RIT. In Chapter 5, RIT was than compared to HIPEC, where survival after CS was significantly improved by RIT whereas adjuvant HIPEC did not and was more toxic than RIT. In Chapter 6, the effects of adjuvant RIT or HIPEC after CS on the healing of bowel anastomoses and abdominal wall was investigated. We concluded that RIT is superior to HIPEC regarding anastomotic and abdominal wall wound strength in a model of PC of CRC. In Chapter 7 we investigated whether carbohydrate modifications of the antibody could improve pharmacokinetics of the intraperitoneally administered antibody. This resulted in improved tumor-non-tumor ratios and thus might improve RIT, especially in combination with short-lived non-residualizing radionuclides. The data of a patient study where a two-step pretargeting radioimmunoscintigraphy technique was used, are presented in Chapter 8, where the optimal time interval between the administration of the antibody and the radiolabeled peptide was investigated in patients with colorectal cancer. These data show the best time interval to be four days after Ab injection.With bibliogr., with summaries in English and Dutch. - Dissertation Radboud University Nijmegen172 p

Computer-assisted proofs of performance ratios for the differencing method

We consider the problem of partitioning a set of nn numbers into mm subsets of cardinality k=⌈n/m⌉k=⌈n/m⌉ or ⌊n/m⌋⌊n/m⌋, such that the maximum subset sum is minimal. We show that the performance ratio of the Differencing Method of Karmarkar and Karp for solving this problem is at least View the MathML source2−∑i=0k−1i!k! for any fixed kk. We also build a mixed integer linear programming model (milp) whose solution yields the performance ratio for any given kk. For k≤7k≤7 these milp-instances can be solved with an exact milp-solver. This results in a computer-assisted proof of the tightness of the aforementioned lower bound for k≤7k≤7. For k>7k>7 we prove that View the MathML source2−1k−1 is an upper bound on the performance ratio, thereby leaving a gap with the lower bound of Θ(k−3)Θ(k−3), which is less than 0.4%status: publishe

Hyperthermia and fibrinolytic therapy do not improve the beneficial effect of radioimmunotherapy following cytoreductive surgery in rats with peritoneal carcinomatosis of colorectal origin.

Contains fulltext : 69926.pdf (publisher's version ) (Open Access)BACKGROUND AND OBJECTIVE: Cytoreductive surgery (CS) and heated intraperitoneal chemotherapy (HIPEC) are standard treatment for peritoneal carcinomatosis (PC) of colorectal cancer. Previously, we demonstrated that preclinical radioimmunotherapy (RIT) adjuvant to surgery in PC is a good alternative for HIPEC. Now we aimed to improve the effectiveness of RIT by combining it with whole-body hyperthermia (WBH) or fibrinolytic therapy. METHODS: Rats were inoculated intraperitoneally with colon carcinoma cells. Animals underwent CS, CS + WBH (40 degrees C, 3 hours), CS + RIT (74 MBq 177Lu-labeled MG1), or CS + WBH + RIT. In the second experiment, rats underwent CS, CS + RIT, CS + recombinant tissue plasminogen activator (rtPA, twice daily, 3 days), or CS + RIT + rtPA. RESULTS: Median survival after CS and CS + WBH was 34 and 37 days. Median survival after CS + RIT or CS + RIT + WBH was 63 and 86 days (p < 0.0003, p < 0.0006 compared to CS + WBH). Median survival after CS and CS + rtPA was 50 and 42 days (p = 0.1). Median survival was 106 days after CS + RIT and 103 days after CS + RIT + rtPA (p < 0.0001 compared to CS + rtPA). No difference was found between CS + RIT and CS + RIT + rtPA (p = 0.83). CONCLUSIONS: The application of WBH or rtPA in combination with adjuvant RIT after CS for the treatment of PC of colonic was feasible but did not significantly potentiate the efficacy of RIT