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The fast reactor is gradually being paid attention to in nuclear power due to a better breeding effect, and its economy is also directly followed. Due to the restriction of the core power density, the core power level is directly related to the volume of the core active area. When the power level and the volume of the core gradually increase, the mass of uranium and 235U in the core at the beginning of life will gradually increase on the basis of a critical uranium inventory. At the same time, due to the gradual increase in the breeding effect, the utilization rate of uranium resources at the end of life will gradually increase. Due to the characteristics of the large critical uranium mass and high breeding effect, the mass of uranium and 235U in the low power level core at the beginning of life cannot be further reduced because of the critical uranium inventory. The lifetime of the high power level core should be extended to use the wealthy reactivity of the core because of the improvement in the breeding effect. However, due to the requirements of the nuclear power refuel time and the limitation to fuel consumption, the breeding effect brought by the improvement in the core power level and the size of the active zone may be less effective. In this article, the power level and economy of lead-based modular nuclear power are analyzed, and the economy of different power level fast reactors with 2,000 EFPD lifetime such as 100 MWt, 300 MWt, 500 MWt, 700 MWt, and 1000 MWt thermal power is designed and analyzed. By analyzing the invention of uranium and 235U and the fuel utilization of different core schemes, the best economic analysis of the single reactor power of the current lead-based modular reactor is proposed and the foundation of the lead-based modular nuclear power is provided.

Yanzhao Zhou,1,* Yi Yang,2,* Bingyan Zhou,3 Zhengzheng Wang,1 Ruili Zhu,1 Xun Chen,1 Jingzhong Ouyang,1 Qingjun Li,1 Jinxue Zhou1 1Department of Hepatobiliary and Pancreatic Surgery, Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan Province, 450008, People’s Republic of China; 2Department of Interventional Therapy, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, People’s Republic of China; 3School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, 450001, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jinxue ZhouDepartment of Hepatobiliary and Pancreatic Surgery, Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan Province, 450008, People’s Republic of ChinaEmail zhoujx888@126.comAbstract: As an emerging minimally invasive treatment method, percutaneous ablation is more and more widely used in the treatment of liver tumors. It has been recommended by guidelines for diagnosis and treatment of hepatocellular carcinoma (HCC) as a curative treatment alongside surgical resection and liver transplantation. In recent years, with the continuous advancement and innovation of percutaneous ablation technologies, their clinical efficacy and safety have been significantly improved, which has led to the expanded application of percutaneous ablation in the treatment of HCC—more and more patients who were previously considered unsuitable for ablation therapies are now being treated with percutaneous ablation. Obviously, percutaneous ablation can reduce the risk of treatment changes from curative strategies to palliative strategies. Based on clinical practice experience, this review enumerates the advantages and disadvantages of different ablative modalities and summarizes the existing combinations of ablation techniques, thus will help clinicians choose the most appropriate ablative modality for each patient and will provide scientific guidance for improving prognosis and making evidence-based treatment decisions. In addition, we point out the challenges and future prospects of the ablation therapies, thereby providing direction for future research.Keywords: percutaneous ablation, hepatocellular carcinoma, assistive technology, image guidance

Background Scar-related Intra-atrial re-entrant tachycardias (IARTs) located at lateral wall of right atrium are common late after cardiac surgery in which right lateral atriotomy was performed, and also occurred in some patients without prior atriotomy. Conventional mapping and ablation is relatively difficult because of the complicated anatomy and multiple potential re-entry loops. Objective The study aims to investigate a new method of strategic linear ablation to isolation of scar area from right lateral wall for successful ablation of scar-related atrial tachycardia originating at lateral wall of right atrium. Methods Four patients had AT related to myocardial scar or incision located at lateral wall of right atrium underwent the electrophysiological study and RF catheter ablation. Earliest activation combined with entrainment mapping was adopted to determine a critical isthmus. Scar area isolation from right lateral wall was performed by linear ablation along cavotricuspid isthmus, from the scar to crista terminalis and to the inferior vena cava (IVC), from the scar to the tricuspid annulus. Results Fifteen IARTs was induced in all of four patients. Four of 15 atrial tachycardias (ATs) were intra-scar reentry AT, three typical atrial flutter (AFL), two double loop reentry tachycardia (DLR) around superior vena cava (SVC) and inferior vena cava (IVC) respectively, four upper loop reentry tachycardia (ULR) around SVC, two lower loop reentry tachycardia (LLR) around IVC. The reentry loops of all ATs were related with scar area. The mean tachycardia cycle length was 268.1±49.5 ms. In all patients, linear ablations along cavotricuspid isthmus, from scar area to crista terminalis and to IVC, were performed. Linear ablation from scar area to tricuspid annulus was performed in one patient. Isolation of scar area from right lateral wall was achieved in all patients. All tachycardias, including scar-related AT and typical AFL were ablated successfully. There was no complication during procedure. No recurrences of AT was observed during follow-up. Conclusion Under conventional electrophysiological mapping, linear ablations from scar area to anatomic barrier and/or isolation of scar area from right lateral wall, could be successfully abolish IARTs and all potential circuits with reentry around or related to the scar.

Background With the number of complex catheter ablation procedures increasing, procedure-related acute cardiac tamponade is encountered more frequently in the cardiac catheterisation laboratory. Survival depends on prompt recognisation and rescue pericardiocentesis. Objective The aim of this report was to validate fluoroscopic heart silhouette characteristics associated with cardiac tamponade as a diagnostic method, and evaluate the safety and effectiveness of fluoroscopy-guided pericardiocentesis during catheter ablation. Methods All cases of acute cardiac tamponade that occurred in the cardiac catheterisation laboratory during radiofrequency catheter ablation from March 2004 to November of 2009 were reviewed retrospectively. Results Of 1832 catheter ablation procedures performed during a 5-year period, 10 (0.55%) were complicated by cardiac tamponade. Fluoroscopic examination confirmed the diagnosis in all 10 patients and demonstrated effusions before hypotension In 4 patients. All patients were stabilised by fluoroscopy-guided pericardiocentesis with placement of an indwelling catheter and autologous transfusion. The time interval between recognition of cardiac tamponade and completion of pericardiocentesis was 6.0±1.8 min (range 3–9 min). The mean aspirated blood volume was 437 ml (range 110–1400 ml), and the mean autotransfused blood volume was 425 ml (range 100–1384 ml). Surgical repair of the cardiac perforation was needed in one patient. No procedure-related death occurred. The ablation procedures were resumed and succeeded in 3 patients after pericardiocentesis. Conclusion A reduction in the excursion of cardiac silhouette on fluoroscopy is an early diagnostic sign of cardiac tamponade during radiofrequency ablation. Fluoroscopy-guided pericardiocentesis is a safe and effective management strategy for cardiac tamponade developed in the cardiac catheterisation laboratory.