The role of nano-perovskite in the negligible thorium release in seawater from Greek bauxite residue (red mud)

We present new data about the chemical and structural characteristics of bauxite residue (BR) from Greek Al industry, using a combination of microscopic, analytical, and spectroscopic techniques. SEM-EDS indicated a homogeneous dominant “Al-Fe-Ca-Ti-Si-Na-Cr matrix”, appearing at the microscale. The bulk chemical analyses showed considerable levels of Th (111 μg g−1), along with minor U (15 μg g−1), which are responsible for radioactivity (355 and 133 Bq kg−1 for 232Th and 238U, respectively) with a total dose rate of 295 nGy h−1. Leaching experiments, in conjunction with SFICP- MS, using Mediterranean seawater from Greece, indicated significant release of V, depending on S/L ratio, and negligible release of Th at least after 12 months leaching. STEM-EDS/EELS & HR-STEMHAADF study of the leached BR at the nanoscale revealed that the significant immobility of Th4+ is due to its incorporation into an insoluble perovskite-type phase with major composition of Ca0.8Na0.2TiO3 and crystallites observed in nanoscale. The Th LIII-edge EXAFS spectra demonstrated that Th4+ ions, which are hosted in this novel nano-perovskite of BR, occupy Ca2+ sites, rather than Ti4+ sites. That is most likely the reason of no Th release in Mediterranean seawater

Association between biliary complications and technique of hilar division (extrahepatic vs. intrahepatic) in major liver resections

BACKGROUND: Division of major vascular and biliary structures during major hepatectomies can be carried out either extrahepatically at the porta hepatic or intrahepatically during the parenchymal transection. In this retrospective study we test the hypothesis that the intrahepatic technique is associated with less early biliary complications. METHODS: 150 patients who underwent major hepatectomies were retrospectively allocated into an intrahepatic group (n = 100) and an extrahepatic group (n = 50) based on the technique of hilar division. The two groups were operated by two different surgical teams, each one favoring one of the two approaches for hilar dissection. Operative data (warm ischemic time, operative time, blood loss), biliary complications, morbidity and mortality rates were analyzed. RESULTS: In extrahepatic patients, operative time was longer (245 ± 50 vs 214 ± 38 min, p < 0.05) while the overall complication rate (55% vs 52%), hospital stay (13 ± 7 vs 12 ± 4 days), bile leak rate (22% vs 20%) and mortality (2% vs 2%) were similar compared to intrahepatic patients. However, most (57%) bile leaks in extrahepatic patients were grade II (leaks that required non-operative interventional treatment, while most (70%) leaks in the intrahepatic group were grade I (leaks that resolved and presented two injuries (4%) of the remaining bile ducts (p < 0.05). CONCLUSION: Intrahepatic hilar division is as safe as extrahepatic hilar division in terms of intraoperative blood requirements, morbidity and mortality. The extrahepatic technique is associated with more severe bile leaks and biliary injuries

Liver preconditioning with prostaglandin I2 for liver resection with pringle monuevre

This is the first experimental trial focusing on the effects that the intravenous use of Prostaglandin h might have just before the clamping of the portal triad for an extended hepatectomy (>50%) We used three groups of Lard race pigs in the first one we performed ar\ extended hepatectomy in a standard way while in the two others there was a parenchymal pretreatment with PGh via a central vein and right into the portal vein just before we performed the operation Blood samples were taken at four different times during the operation and on the 1st 2nd 5th and 7th postoperative day The last day we sacrificed the animal and tissue samples were taken for histological examination The whole hepatic function was analyzed and interleukms were also measured Statistical analysis of the results revealed that liver function was improved in the two study groups compared with the control group as this is shown through the values of the 5GOT SGPT PT APTT TNF-a IL-la and IL-6 which were statistically significant (p50%) is a safe way to increase the liver remnants function by decreasing the effects of ischemia/reperfusion syndromeΗ παρούσα διατριβή πραγματεύεται για πρώτη φορά την προεγχειρητικη χρήση ενός ανάλογου της προσταγλανδινης h για την προετοιμασία του ηπατικού παρεγχύματος πριν απο εκτεταμένη ηπατεκτομή Η μελέτη εκτελέστηκε σε χοίρους Υπήρξαν τρεις ομάδες των 7 χοίρων έκαστη στην πρώτη δε χορηγήθηκε προσταγλανδινη, ενω στη 2^ χορηγήθηκε στη συστηματική κυκλοφορία και στην 3*ι απευθείας στην πυλαία φλέβα πριν απο το χειρισμό Pringle Στα ζωα διενεργήθηκε εκτεταμένη ηπατεκτομή >50% (60-65%) με εφαρμογή αγγειακού αποκλεισμού (Pringle) για 40 λεπτά Οι παράμετροι που μετρήθηκαν περιλαμβάνουν ολο το φάσμα της βιοχημικής λειτουργίας του ήπατος, καθώς επίσης και τις κυττοκινες TNF-α, IL-la και IL-6 Κατά τη θανάτωση του ζώου την έβδομη μετεγχειρητική ήμερα ελήφθησαν βιοψίες ήπατος, που απεστάλησαν για ιστολογική μελέτη και μέτρηση πυρηνοκινησιων (PCNA) Απο τα αποτελέσματα εξήχθησαν στατιστικώς σημαντικές διάφορες, ανάμεσα στην ομάδα που δε χορηγήθηκε προετοιμασία και στις ομάδες εργασίας, για τις τιμές των ηπατικών ένζυμων, καθώς επίσης και για τις ιντερλευκινες τέτοιες που συνηγορούν υπέρ της αδιαμφισβήτητης βελτίωσης της ηπατικής λειτουργίας απο την προεγχειρητικη χορήγηση και Οραση της PGb Παράκλησ

The role of nano-perovskite in the negligible thorium release in seawater from Greek bauxite residue (red mud)

We present new data about the chemical and structural characteristics of bauxite residue (BR) from Greek Al industry, using a combination of microscopic, analytical, and spectroscopic techniques. SEM-EDS indicated a homogeneous dominant "Al-Fe-Ca-Ti-Si-Na-Cr matrix", appearing at the microscale. The bulk chemical analyses showed considerable levels of Th (111 μg g(-1)), along with minor U (15 μg g(-1)), which are responsible for radioactivity (355 and 133 Bq kg(-1) for (232)Th and (238)U, respectively) with a total dose rate of 295 nGy h(-1). Leaching experiments, in conjunction with SF-ICP-MS, using Mediterranean seawater from Greece, indicated significant release of V, depending on S/L ratio, and negligible release of Th at least after 12 months leaching. STEM-EDS/EELS &HR-STEM-HAADF study of the leached BR at the nanoscale revealed that the significant immobility of Th(4+) is due to its incorporation into an insoluble perovskite-type phase with major composition of Ca(0.8)Na(0.2)TiO3 and crystallites observed in nanoscale. The Th L(III)-edge EXAFS spectra demonstrated that Th(4+) ions, which are hosted in this novel nano-perovskite of BR, occupy Ca(2+) sites, rather than Ti(4+) sites. That is most likely the reason of no Th release in Mediterranean seawater.status: publishe