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Strategic decisions regarding fuels used to meet the University of Virginia's current and future steam demand require an in-depth understanding of the operations of the University of Virginia's Main Heat Plant. The current mix of fossil fuels that the Main Heat Plant depends on to heat the University is constrained in numerous ways, including: the University of Virginia's natural gas allotments, the contractual curtailments on natural gas set by the City of Charlottesville, the University of Virginia's commitment to reducing greenhouse gas emissions, and financial costs. This paper focuses on developing an 8760 (24 hours × 365 days) model that compares multiple what-if scenarios on key measures through simulating the performance of the plant during a year at one hour increments. These scenarios evaluate the effects of changes to the aforementioned constraints and also to increases in demand. Operators at the Main Heat Plant will use the model through an interface that allows them to observe the performance of the system and explore different alternatives by selecting specific scenarios. Summary graphics for parameters such as greenhouse gas emissions, fuel usage, and cost provide decision makers in the plant and in University of Virginia administration with information needed to make strategic decisions regarding the Main Heat Plant and related fuel agreements. The simulated results were validated through a comparison against actual data collected from July 2016 to June 2017, resulting in 65% of modeled fuel states, matching the historical fuel states for the same periods.

Background To consolidate literature reports of serious late gastrointestinal toxicities after hypofractionated radiation treatment of pancreatic cancer and attempt to derive normal tissue complication probability (NTCP) parameters using the Lyman-Kutcher-Burman model. Methods Published reports of late grade 3 or greater gastrointestinal toxicity after hypofractionated treatment of pancreatic cancer were reviewed. The biologically equivalent dose in 1.8 Gy fractions was calculated using the EQD model. NTCP parameters were calculated using the LKB model assuming 1–5 % of the normal tissue volume was exposed to the prescription dose with α/β ratios of 3 or 4. Results A total of 16 human studies were examined encompassing a total of 1160 patients. Toxicities consisted of ulcers, hemorrhages, obstructions, strictures, and perforations. Non-hemorrhagic and non-perforated ulcers occurred at a rate of 9.1 % and were the most commonly reported toxicity. Derived NTCP parameter ranges were as follows: n = 0.38–0.63, m = 0.48–0.49, and TD50 = 35–95 Gy. Regression analysis showed that among various study characteristics, dose was the only significant predictor of toxicity. Conclusions Published gastrointestinal toxicity reports after hypofractionated radiotherapy for pancreatic cancer were compiled. Median dose was predictive of late grade ≥ 3 gastrointestinal toxicity. Preliminary NTCP parameters were derived for multiple volume constraints.

A 28-year-old female who underwent live donor liver transplantation 3 years prior presented after percutaneous liver biopsy with abdominal and shoulder pain, nausea, vomiting, and elevated liver enzymes. Computed tomography (CT) showed an intrahepatic and subcapsular hematoma. There was a progressive increase in liver enzymes, bilirubin, and INR and a decline in hemoglobin. Subsequent CT imaging revealed flattening of the portal vein consistent with compression by the enlarging hematoma. Liver failure ensued and the patient required urgent retransplantation. The explant demonstrated ischemic necrosis of greater than 90% of the liver parenchyma. We report this case of “Hepatic Compartment Syndrome” leading to fulminant hepatic failure.