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In the petrochemical industry, control room operators must address safety-critical alarms and other tasks using complex interfaces. This study developed a guide for assessing human performance using standard human factors measurement tools, and tested the sensitivity of those tools with two interface designs (i.e., gray and black) at three levels of workload (i.e., easy, medium, and difficult). The guide measures human performance through speed and accuracy, perceived workload using two standard instruments (i.e., NASA Task Load Index (NASA-TLX) and Subjective Workload Assessment Technique (SWAT)), situation awareness through the Situation Awareness Global Assessment Technique (SAGAT), and gaze through eye tracking coordinates. Twelve engineering student participants completed one simulation session at each of the three workload levels using one of two interface designs. Workload was manipulated through the number of simulated events (failures) in each session. Overall, the speed and accuracy measures, workload ratings, and eye tracking showed sensitivity to differences in workload level, and situation awareness showed sensitivity to the interaction between workload level and interface type. None of the tools were sensitive to interface type alone. Accuracy was highest under easy workload. Time per failure decreased at higher workload levels. Perceived workload ratings from the SWAT increased as workload increased, but workload ratings from the NASA-TLX were not different across workload levels. When workload increased, situation awareness remained steady for the gray interface but decreased sharply for the black interface, illustrating an interaction effect. Finally, the percentage of time spent looking at different areas of the screen during steady-state periods differed among workload levels. The tools in this guide can be used in the petrochemical industry to make design decisions for control room interfaces when workload levels are a concern.

Gallstone spillage is recognised as a possible complication of laparoscopic cholecystectomy and there are countless examples of untoward short and long term sequelae resulting from their non-retrieval. We present the case of a 65-year-old gentleman with sterile pyuria and lower midline abdominal mass which proved to be a complex gallstone inflammatory mass related to the dome of the bladder. This patient’s investigative course was exhaustive and the definitive diagnosis not achieved until histopathological assessment of the intraoperative specimen. The diagnosis of these lower abdominal wall masses can be difficult, particularly with complex lesions.

The ability of anti-T cell monoclonal antibody G4.18 and polyclonal anti-lymphocyte serum (ALS) to induce long-term graft survival was examined in a high-responder rat heart transplant model. Heterotopic heart allografts were performed from PVG rat strain donors to high-responder Lewis recipients. Immunosuppressive properties of G4.18 and ALS were investigated by immunohistochemistry and PCR analysis. Untreated graft rejection was 8.5 days while treatment with 1 ml ALS prolonged survival to 11.5 days (p = 0.01). Treatment with 7 mg/kg G4.18 on days 1 and 3 prolonged survival to > 100 days (p = 0.002 vs. control and p = 0.002 vs. ALS) but did not induce tolerance. Acceptance was associated with marked inhibition of cellular infiltration and inflammatory cytokine expression and only a brief, slight increase in Foxp3:T cell ratio in the graft and no increase in the spleen. In conclusion, G4.18 treatment led to long-term heart transplant survival associated with marked inhibition of early inflammation. Failure to develop tolerance was associated with a lack of early accumulation of Foxp3 cells in the graft or spleen.