Enhanced Nuclear Engineering Simulators

Engineering simulation is a sophisticated multi-purpose technology allowing the users of simulators to run a variety of engineering activities due to the possibility of modifying the simulated plant architecture and components, to adjust parameters, to test alternative solutions. Engineering Simulators (ES) have been built and used worldwide for a variety of purposes: - Development and refinement of the plant design or plant modifications - Safety analyses focused on the overall system behaviour - Verification and Validation (V&V) of systems and components - Development of Operational and Emergency Procedures - Pre-Training of operators and supervisors - High level education and Communication activities - Human Factor Engineering Analysis - Adaptive Control System training Engineering Simulators also play a role in developing and maintaining key nuclear skills, as knowledge repositories and tools for training at various levels of expertise

Xenotransplantation transgenesis. Are we there yet?

Nottle MB, Hawthorne W, O'Connell PJ, d'Apice AJF, and Cowan P

Mitochondrial a kinase anchor proteins in cardiovascular health and disease: a review article on behalf of the Working Group on Cellular and Molecular Biology of the Heart of the Italian Society of Cardiology

Second messenger cyclic adenosine monophosphate (cAMP) has been found to regulate multiple mitochondrial functions, including respiration, dynamics, reactive oxygen species production, cell survival and death through the activation of cAMP-dependent protein kinase A (PKA) and other effectors. Several members of the large family of A kinase anchor proteins (AKAPs) have been previously shown to locally amplify cAMP/PKA signaling to mitochondria, promoting the assembly of signalosomes, regulating multiple cardiac functions under both physiological and pathological conditions. In this review, we will discuss roles and regulation of major mitochondria-targeted AKAPs, along with opportunities and challenges to modulate their functions for translational purposes in the cardiovascular system

Natural experiments for the evaluation of place-based public health interventions:a methodology scoping review

Place-based public health evaluations are increasingly making use of natural experiments. This scoping review aimed to provide an overview of the design and use of natural experiment evaluations (NEEs), and an assessment of the plausibility of the as-if randomisation assumption. A systematic search of three bibliographic databases (Pubmed, Web of Science and Ovid-Medline) was conducted in January 2020 to capture publications that reported a natural experiment of a place-based public health intervention or outcome. For each, study design elements were extracted. An additional evaluation of as-if randomisation was conducted by twelve 12 of this paper’s authors who evaluated the same set of 20 randomly selected studies and assessed ‘as-if’ randomisation for each. 366 NEE studies of place-based public health interventions were identified. The most commonly used NEE approach was a Difference-in-Differences study design (25%), followed by before-after comparisons studies (23%) and regression analysis studies. 42% of NEEs had likely or probably as-if randomisation of exposure (the intervention), while for 25% this was implausible. An inter-rater agreement exercise indicated poor reliability of as-if randomisation assignment. Only about half of NEEs reported some form of sensitivity or falsification analysis to support inferences. NEEs are conducted using many different designs and statistical methods and encompass various definitions of a natural experiment, while it is questionable whether all evaluations reported as natural experiments should be considered as such. The likelihood of as-if randomisation should be specifically reported, and primary analyses should be supported by sensitivity analyses and/or falsification tests. Transparent reporting of NEE designs and evaluation methods will contribute to the optimum use of place-based NEEs

Priority Queueing System with Many Types of Requests and Restricted Processor Sharing

A priority queueing model with many types of requests and restricted processor sharing is considered. A novel discipline of requests admission and service is proposed. This discipline assumes restriction of the bandwidth (capacity) of the server and the number of requests that can receive service in the system at the same time. This discipline is some kind of realistic hybrid of the traditional discipline of service in a multi-server system and the discipline of the limited processor sharing. The requests of the highest priority can push out from the service the low priority requests. Therefore, the important problem is fitting of the number of requests that can receive service at the same time to the bandwidth of the server. This problem is solved via construction and analysis of a multi-dimensional Markov chain describing operation of the system under any fixed set of the system parameters

An Enhanced Nuclear Engineering Simulator

Engineering Simulation is a sophisticated multi-purpose technology allowing the users of simulators to run various engineering activities thanks to the possibility of representing the behavior of the plant under normal and adverse conditions, and of modifying the simulated plant architecture and components, adjust a huge set of parameters, test alternative operational solutions. Engineering Simulators have been developed worldwide for performing plant design, integrated safety analysis, verification and validation of systems and components and human factors studies. These tools also play a role in developing and maintaining key nuclear skills, as knowledge repositories for training at various levels of expertise. The ‘ENES’ Strategic Project (proposed by ENEA within NUGENIA framework) aims at designing in detail the most urgent improvements to the current generation of Engineering Simulators for Gen II – Gen III NPPs in order to define the key characteristics of a new generation of Enhanced Simulators that can respond adequately to the various issues raised by the Fukushima accident and to other key targets of the international agenda for nuclear plants safety

Arteriolopatia calcifica uremica: un'entità clinica rara?

Calcific uremic arteriolopathy (Calcyphilaxis): a rare disease? Report of three cases INTRODUCTION: Calcific uremic arteriolopathy (CUA; CALCYPHILAXIS) is a syndrome that occurs prevalently in patients with chronic kidney disease on dialysis. It is characterized by the medial calcification of skin small arteries leading to necrotic lesions. Several risk factors have been identified: obesity, female gender, diabetes mellitus, hyperphosphatemia, inflammation, treatment with vitamin D, calcium-based phosphate binders and warfarin. MATERIALS AND METHODS: We report three cases of CUA observed from October 2011 to September 2014. RESULTS: The mean age at diagnosis was 56 years (range 33-68). Biochemistry showed: mean levels of PTH=1277 pg/ml (range 1000-1696), serum calcium =10.2 mg/dl (range 9.4-11.1), phosphorus=4.5 mg/dl (range 3.4-5.5). All patients were taking vitamin D, two patients were on warfarin therapy. Following actions were undertaken: interruption of calcium-based phosphate binders, vitamin D and warfarin therapy, initiation of cinacalcet and sodium thiosulfate therapy, use of dialysate with lowest available calcium concentration (1.25 mmol/l), Hyperbaric Oxygen Therapy, surgical dressings of skin lesions three times a week. Significant improvement was observed in mean levels of PTH (331 pg/ml, range 200-465), serum calcium (8.3 mg/dl, range 7.4-9.6) and phosphorus (3.4 mg/dl, range 2.6-3.8). In two out of three patients complete healing of ulcerative lesions was obtained. CONCLUSIONS: These cases underline the importance of early diagnosis of CUA especially in patients with concomitant risk factors and careful clinical monitoring, being CUA characterized by a rapid evolution and high mortalit