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This study quantifies the environmental risk of a coal-fired thermal power plant during operation by using environmental monitoring data, site surveys, and documented evidence. The following criteria are assessed: emissions (CO, SO2 , NOx , PM10 ), impact on aquatic ecosystem (fish protection at cooling water intake and cooling water discharge temperature), and waste management (fly ash and bottom ash). Fuzzy sets were defined for each criterion, taking environmental regulatory context as an expert judgment. A survey was conducted with multiple stakeholders to determine the relative importance of risk factors. The survey results showed that the most concerned risks are SO2 and NOx emissions. The proposed method estimates the risk of each environmental criterion separately and then accumulates them into an environmental risk index (ERI). Accordingly, we assessed the Catalagzi coal-fired power plant, which has been in operation on the Black Sea coast in northwestern Turkey. For this case study, the ERI resulted in a value of 0.78 (on a scale of 0-1), showing high environmental risk to the facility. Moreover, the applicability of the proposed framework was tested in several existing coal-fired power plants using simultaneous measurements. All studied coal-fired power plants in Turkey have unacceptable pollutants (PM10 , SO2 , and NOx ) concentration levels indicating high health risk potential. The application of the integrated environmental risk assessment framework showed that new environmental regulations are needed in Turkey to specify more strict emission limits and to monitor CO2 , fine particulate matter emissions, cooling water discharge, and fish protection at cooling water intake.
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BACKGROUND: There is increasing interest in transplanting patients with hepatocellular carcinoma (HCC) with tumors greater than 5 cm (Milan criteria). AIM: To investigate possible prognostically-useful factors for liver transplantation in HCC patients with large tumors. METHODS: In this clinical study, 50 patients with HCC who were transplanted at our Liver Transplant Center between April 2006 and August 2019 and had tumors greater than 6 cm maximum diameter were retrospectively analyzed. Their survival and full clinical characteristics were examined, with respect to serum alpha-fetoprotein (AFP) and gamma glutamyl transpeptidase (GGT) levels. Kaplan-Meier survival estimates were used to determine overall survival and disease-free survival in these patients. The inclusion criterion was evidence of HCC. Exclusion criteria were the presence of macroscopic portal vein thrombosis or metastasis and a follow-up period of less than 90 d. RESULTS: Using receiver operating characteristic curve (ROC) analysis, cutoff values of AFP 200 ng/mL and GGT 104 IU/L were identified and used in this study. Significantly longer overall survival (OS) and disease-free-survival (DFS) were found in patients who had lower values of either parameter, compared with higher values. Even greater differences in survival were found when the 2 parameters were combined. Two tumor size bands were identified, in searching for the limits of this approach with larger tumors, namely 6-10 cm and > 10 cm. Combination parameters in the 6-10 cm band reflected 5-year OS of 76.2% in patients with low AFP plus low GGT vs 0% for all other groups. Patients with tumors greater than 10 cm, did not have low AFP plus low GGT. The most consistent clinical correlates for longer survival were degree of tumor differentiation and absence of microscopic portal venous invasion. CONCLUSION: Serum levels of AFP and GGT, both alone and combined, represent a simple prognostic identifier in patients with large HCCs undergoing liver transplant-ation.