Genetic Algorithms for Stochastic Flow Shop No Wait Scheduling

ln this paper we present Genetic Algorithms - evolutionary algorithms based on an analogy with natural selection and survival of the fittest - applied to an NP Complete combinatorial optimization problem: minimizing the makespan of a Stochastic Flow Shop No Wait (FSNW) schedule. This is an important optimization criteria in real-world situations and the problem itself is of practical significance. We restrict our applications to the three machine flow shop no wait problem which is known to be NP complete. The stochastic hypothesis is that the processing times of jobs are described by normally distributed random variables. We discuss how this problem may be translated into a TSP problem by using the start interval concept. Genetic algorithms, both sequential and parallel are then applied to search the solution space and we present the algorithms and empirical results

Penetrating Ureteral Trauma.

The purpose of this series is to report our experience in managing ureteral trauma, focusing on the importance of early diagnosis, correct treatment, and the impact of associated injuries on the management and morbid-mortality. From January 1994 to December 2002, 1487 laparotomies for abdominal trauma were performed and 20 patients with ureteral lesions were identified, all of them secondary to penetrating injury. Medical charts were analyzed as well as information about trauma mechanisms, diagnostic routine, treatment and outcome. All patients were men. Mean age was 27 years. The mechanisms of injury were gunshot wounds in 18 cases (90%) and stab wounds in two (10%). All penetrating abdominal injuries had primary indication of laparotomy, and neither excretory urography nor computed tomography were used in any case before surgery. The diagnosis of ureteric injury was made intra-operatively in 17 cases (85%). Two ureteral injuries (10%) were initially missed. All patients had associated injuries. The treatment was dictated by the location, extension and time necessary to identify the injury. The overall incidence of complications was 55%. The presence of shock on admission, delayed diagnosis, Abdominal Trauma Index > 25, Injury Severity Score > 25 and colon injuries were associated to a high complication rate, however, there was no statistically significant difference. There were no mortalities in this group. A high index of suspicion is required for diagnosis of ureteral injuries. A thorough exploration of all retroperitoneal hematoma after penetrating trauma should be an accurate method of diagnosis; even though it failed in 10% of our cases.33142-8, discussion 149-5

Gleason Score As Predictor Of Clinicopathologic Findings And Biochemical (psa) Progression Following Radical Prostatectomy.

There is evidence showing that Gleason grading of prostatic adenocarcinoma is one of the most powerful predictors of biological behavior and one of the most influential factors used to determine treatment for prostate cancer. The aim of the current study was to compare the Gleason score for needle biopsy to the Gleason score for the correspondent surgical specimen, find any possible difference in the biochemical (PSA) progression following surgery in upgraded cases, correlate Gleason score in the specimens to several clinicopathologic variables, and compare outcomes between patients with low-grade vs. high-grade Gleason and Gleason scores 3+4 vs. 4+3. The study population consisted of 200 consecutive patients submitted to radical prostatectomy. Biochemical progression was defined as PSA > or = 0.2 ng/mL. Time to PSA progression was studied using the Kaplan-Meier product-limit analysis. In 47.1% of the cases, there was an exact correlation and 40.6% of cases were underestimated in the biopsies. Half of the tumors graded Gleason 6 at biopsy were Gleason score 7 at surgery. These upgraded tumors had outcomes similar to tumors with Gleason score 7 in both biopsy and surgery. There was a positive correlation of high-grade Gleason score in the surgical specimens to higher preoperative PSA, more extensive tumors, positive margins and more advanced pathologic staging. Tumors with a Gleason score > or = 7 have lower PSA progression-free survival vs. Gleason scores < 7. In this series, there was no significant difference when comparing Gleason scores of 3+4 vs. 4+3. The findings support the importance of Gleason grading for nomograms, which are used by clinicians to counsel individual patients and help them make important decisions regarding their disease.3423-