First Experience with the Consolidation of WWER Reactor Pressure Vessel Knowledge through a New Method

One of today¿s activities of the Joint Research Centre¿s (JRC) Institute for Energy (IE) concerns data management and dissemination in nuclear safety. An ¿Online Data & Information Network¿ (ODIN) is set-up, which maintains one document database and four engineering databases. These databases aim to deploy networks for energy related research & development, specifically for nuclear energy and to provide the public experimental data of European projects on mechanical and thermo-physical material properties in comparison with international standards and recommendations. Due to its long lasting experience and being in a key position as regards web based d-base (e.g. ODIN), the IAEA for example has recently transferred the reactor surveillance data-base to the IE. Lately, many stakeholders, such as Institutes, R&D Organisations, Regulators, Utilities, Governmental Organisations, have recognised the need for collecting, preserving, consolidating (validating), and disseminating nuclear knowledge (documents, competences and data), in order to make it easily accessible to future generations through modern informatics tools and training and education measures. A broad spectrum of components and technologies should be considered, i.e. reactor pressure vessel (RPV), piping, internals, steam generator, etc. regarding knowledge, material data and practices. In the long run, it will also support future decommissioning exercises of nuclear installations as a valuable knowledge source. In addition to the knowledge in each Member State, the IE produced a long standing record of results from its own institutional activities and even more through the participation to a large number of European Network partnership projects. It is important, besides preservation, to consolidate the enormous amount of scientific results produced since. Therefore, the IE has developed a method for consolidation of nuclear knowledge. The method relays on the mobilisation of all identified leading experts in the EU in re-evaluating old knowledge and consolidating what is necessary to create training materials for the new generations. This method was applied for a pilot study for consolidating and preserving WWER RPV safety related knowledge, which is scattered in many countries and in different languages, facing a serious issue in terms of getting lost. This initiative could be the start of a wider Nuclear Knowledge Preservation and Consolidation activity. Experience gained from the first exercise will be presented in this paper.JRC.F.4-Safety of future nuclear reactor

Transcript expression of vesicular glutamate transporters in lumbar dorsal root ganglia and the spinal cord of mice – Effects of peripheral axotomy or hindpaw inflammation

Using specific riboprobes, we characterized the expression of vesicular glutamate transporter (VGLUT)1–VGLUT3 transcripts in lumbar 4–5 (L4–5) dorsal root ganglions (DRGs) and the thoracolumbar to lumbosacral spinal cord in male BALB/c mice after a 1- or 3-day hindpaw inflammation, or a 7-day sciatic nerve axotomy. Sham animals were also included. In sham and contralateral L4–5 DRGs of injured mice, VGLUT1-, VGLUT2- and VGLUT3 mRNAs were expressed in ∼45%, ∼69% or ∼17% of neuron profiles (NPs), respectively. VGLUT1 was expressed in large and medium-sized NPs, VGLUT2 in NPs of all sizes, and VGLUT3 in small and medium-sized NPs. In the spinal cord, VGLUT1 was restricted to a number of NPs at thoracolumbar and lumbar segments, in what appears to be the dorsal nucleus of Clarke, and in mid laminae III–IV. In contrast, VGLUT2 was present in numerous NPs at all analyzed spinal segments, except the lateral aspects of the ventral horns, especially at the lumbar enlargement, where it was virtually absent. VGLUT3 was detected in a discrete number of NPs in laminae III–IV of the dorsal horn. Axotomy resulted in a moderate decrease in the number of DRG NPs expressing VGLUT3, whereas VGLUT1 and VGLUT2 were unaffected. Likewise, the percentage of NPs expressing VGLUT transcripts remained unaltered after hindpaw inflammation, both in DRGs and the spinal cord. Altogether, these results confirm previous descriptions on VGLUTs expression in adult mice DRGs, with the exception of VGLUT1, whose protein expression was detected in a lower percentage of mouse DRG NPs. A detailed account on the location of neurons expressing VGLUTs transcripts in the adult mouse spinal cord is also presented. Finally, the lack of change in the number of neurons expressing VGLUT1 and VGLUT2 transcripts after axotomy, as compared to data on protein expression, suggests translational rather than transcriptional regulation of VGLUTs after injury.Fil: Malet, Mariana. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vieytes, C. A.. Universidad Austral. Facultad de Ciencias Biomédicas; ArgentinaFil: Lundgren, K. H.. University of Cincinnati; Estados UnidosFil: Seal, R. P.. University of Pittsburgh; Estados UnidosFil: Tomasella, María Eugenia. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Seroogy, K. B.. University of Cincinnati; Estados UnidosFil: Hökfelt, T.. Karolinska Huddinge Hospital. Karolinska Institutet; SueciaFil: Gebhart, G. F.. University of Pittsburgh; Estados UnidosFil: Brumovsky, Pablo Rodolfo. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Pittsburgh; Estados Unido

Expression of vesicular glutamate transporters in sensory and autonomic neurons innervating the mouse urinary bladder

Purpose: Vesicular glutamate transporters (VGLUTs), essential for loading glutamate into synaptic vesicles, are present in various neuronal systems. However, the expression of VGLUTs in neurons innervating the urinary bladder has not yet been analyzed. Here, we study the presence of VGLUTs type-1, -2 and -3 (VGLUT1, VGLUT2 and VGLUT3, respectively) in mouse urinary bladder neurons. Materials and Methods: Expression of VGLUT1, VGLUT2 and calcitonin gene-related peptide (CGRP) was analyzed by immunohistochemistry in retrogradely labeled primary afferent and autonomic neurons of BALB/C mice after injecting Fast Blue in the urinary bladder wall. To study VGLUT3, retrograde tracing of the urinary bladder was performed in transgenic mice where VGLUT3 is identified by detection of enhanced green fluorescent protein (EGFP). Results: Most urinary bladder DRG neurons expressed VGLUT2. A smaller percentage of neurons also expressed VGLUT1 or VGLUT3. Coexpression with CGRP was only observed for VGLUT2. Occasional VGLUT2-immunoreactive (IR) neurons were seen in the major pelvic ganglion (MPG). Abundant VGLUT2-IR nerves were detected in the urinary bladder dome, trigone and also the urethra; VGLUT1-IR nerves were discretely present. Conclusions: We present novel data on the expression of VGLUTs in sensory and autonomic neurons innervating the mouse urinary bladder. The frequent association of VGLUT2 and CGRP in sensory neurons suggests interactions between glutamatergic and peptidergic neurotransmissions, potentially influencing commonly perceived sensations in the urinary bladder, such as discomfort and pain.Fil: Brumovsky, Pablo Rodolfo. Universidad Austral. Facultad de Ciencias Biomédicas. Laboratorio de Investigaciones Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados UnidosFil: Seal, Rebecca P.. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados UnidosFil: Lundgren, Kerstin H.. University of Cincinnati. Department of Neurology; Estados UnidosFil: Seroogy, Kim B.. University of Cincinnati. Department of Neurology; Estados UnidosFil: Watanabe, Masahiko. Hokkaido University School of Medicine. Department of Anatomy; JapónFil: Gebhart, G. F.. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados Unido

Annealing and Re-embrittlement of Reactor Pressure Vessel Materials - State of the Art Report

Annealing of a reactor pressure vessel embrittled by neutron irradiation constitutes the only known technique to restore the initial material properties, to an extent that depends on the annealing conditions and on the materials. This technique is used in WWER-440 type reactor pressure vessels. A very important related issue is the one of re-embrittlement behaviour of the material after the annealing. In this respect, there is an obvious link with radiation embrittlement understanding. This report compiles the vast amount of information on annealing and re-embrittlement, which is available in the European countries where such annealing operations have been performed. In addition this topic was also investigated in various TACIS-PHARE projects, and the conclusions are included here as well. To complete the state-of-the-art, the results from a number of annealing experiments carried out in US on Western type RPV steels have also been considered.JRC.F.4-Nuclear design safet

Dorsal root ganglion neurons and tyrosine hydroxylase: An intriguing association with implications for sensation and pain

Tyrosine hydroxylase (TH) is a rate-limiting enzyme broadly expressed in noradrenergic and dopaminergic neurons in the central nervous system.57,70 Tyrosine hydroxylase is also expressed by peripheral sympathetic neurons98 and by enteric neurons within the gut.81,84 More than 30 years ago, TH was unexpectedly discovered in developing adult rodent cranial and dorsal root ganglion (DRG) neurons. Today, TH-expressing DRG neurons are being rediscovered as a relevant subpopulation. This review addresses the emerging importance of TH-expressing DRG neurons in sensation and pain mechanisms, focusing specifically on (1) their nature as C-low threshold mechanoreceptors (C-LTMRs); (2) their involvement in nociception/pain; and (3) their catecholaminergic phenotype.Fil: Brumovsky, Pablo Rodolfo. Universidad Austral. Facultad de Ciencias Biomédicas. Laboratorio de Investigaciones Biomédicas; Argentina. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentin

VERLIFE Guidelines for Integrity and Lifetime Assessment of Components and Piping in WWER Nuclear Power Plants - Appendices A-F

The VERLIFE Guidelines are validated procedures for the calculation of the residual lifetime and integrity of components and piping of WWER–type reactors. They cover procedures for the calculation of the resistance against fast fracture, fatigue damage, corrosion-mechanical damage and acceptability of flaws found during in-service inspection. They also contain procedures for integrity evaluation of piping, in-service inspection qualifications, risk-informed in-service inspection as well as integrity and lifetime of reactor vessel internals and components supports. Numerous appendicies on related specific topics like e.g. degradation assessment of material properties by radiation damage and thermal ageing, thermal hydraulic regimes for pressurized thermal shock evaluations, etc. are part of the guidelines. VERLIFE Guidelines are mainly based on former Soviet/Russian Rules and Codes for design and manufacturing of components and piping of WWER-type reactors. But they also incorporate operational experience of countries with running WWER-type reactors (i.e. Bulgaria, Czech Republic, Finland, Slovakia, Ukraine, …) and to some extent approaches used in codes and rules of pressurised water reactors (PWRs), to be consistent with current PWR codes and rules as much as possible and thus provide modern, applicable procedures for component integrity and residual lifetime assessment of WWER-type plant components and piping. The VERLIFE Guidelines, in full or in parts, may be used for the preparation of official reports to support periodic safety review, licensing and plant life management programmes of WWER-type reactors with the approval of the national nuclear regulatory authority. This publication contains Appendices A-F of the VERLIFE Guidelines: - Appendix A: Leak Before Break (LBB) Concept application to the Selected Piping systems of WWR-type NPPs - Appendix B: No-Break-Area Assessment for WWER Piping - Appendix C: Integrity and Lifetime Assessment Procedure of RPV Internals in WWER-type NPPs during Operation - Appendix D: Risk-Informed In-Service Inspection - Appendix E: NDE System Qualification - Appendix F: Component and Piping Supports This publication is linked to JRC publication JRC 138449, which is the main document of the VERLIFE Guidelines. The latter contains the main chapters and all other appendices, Appendices I – XVIII, of the guidelines. It also contains a description of the structure of the VERLIFE Guidelines and a description of their drafting process.JRC.G.I.4 - Reactor Safety and Component

Project PISA: Phosphorus Influence on Steel Ageing

The integrity of the pressure vessel is vital to the safe operation of a nuclear reactor. It is therefore necessary to monitor or predict the changes in the reactor pressure vessel (RPV) material during operation. Exposure to irradiation (or elevated temperatures) causes the segregation of phosphorus to internal grain boundaries in RPV steels. This, in turn, encourages brittle intergranular failure of the material. The PISA project had the objective of reducing the uncertainties associated with the impact of this failure mechanism on the properties of the RPV, both during service and at the end-of-life. This report presents the experimental results on the segregation of P and C during irradiation and thermal treatments, and the associated mechanical property changes, generated within PISA. The new data cover a range of bulk P levels, irradiation temperatures and fluences, steel types and product forms. In all cases only modest increases of P level on the grain boundary have been observed in commercial steels. Segregation is higher in pre-strained than in unstrained material. In addition a model for P segregation under irradiation has been developed, and shown to be capable of fitting the experimentally observed changes in P level after irradiation. Significant insight into the development of the microstructure under irradiation has thereby been obtained. Overall, the data and modelling together indicated that relatively small amounts of segregation are likely to occur under most reactor operational conditions in homogeneous commercial steels, and an (unexpectedly) small amount of additional embrittlement likely to derive from this process during reactor service.JRC.F.4-Nuclear design safet

VERLIFE Guidelines for Integrity and Lifetime Assessment of Components and Piping in WWER Nuclear Power Plants

The VERLIFE Guidelines are validated procedures for the calculation of the residual lifetime and integrity of components and piping of WWER–type reactors. They cover procedures for the calculation of the resistance against fast fracture, fatigue damage, corrosion-mechanical damage and acceptability of flaws found during in-service inspection. They also contain procedures for integrity evaluation of piping, in-service inspection qualifications, risk-informed in-service inspection as well as integrity and lifetime of reactor vessel internals and components supports. Numerous appendicies on related specific topics like e.g. degradation assessment of material properties by radiation damage and thermal ageing, thermal hydraulic regimes for pressurized thermal shock evaluations, etc. are part of the guidelines. VERLIFE Guidelines are mainly based on former Soviet/Russian Rules and Codes for design and manufacturing of components and piping of WWER-type reactors. But they also incorporate operational experience of countries with running WWER-type reactors (i.e. Bulgaria, Czech Republic, Finland, Slovakia, Ukraine, …) and to some extent approaches used in codes and rules of pressurised water reactors (PWRs) to be consistent with current PWR codes and rules as much as possible and thus provide modern, applicable procedures for component integrity and residual lifetime assessment of WWER-type plant components and piping. The VERLIFE Guidelines, in full or in parts, may be used for the preparation of official reports to support periodic safety review, licensing and plant life management programmes of WWER-type reactors with the approval of the national nuclear regulatory authority. This publication contains the main chapters and Appendices I – XVIII of the VERLIFE Guidelines. Appendices A-F are published as a separate JRC report (JRC 138451).JRC.G.I.4 - Reactor Safety and Component

High pressure intensification of cassava resistant starch (RS3) yields

Cassava starch, typically, has resistant starch type 3 (RS3) content of 2.4%. This paper shows that the RS3 yields can be substantially enhanced by debranching cassava starch using pullulanase followed by high pressure or cyclic high-pressure annealing. RS3 yield of 41.3% was obtained when annealing was carried out at 400 MPa/60°C for 15 min, whereas it took nearly 8 h to obtain the same yield under conventional atmospheric annealing at 60°C. The yield of RS3 could be further significantly increased by annealing under 400MPa/60°C pressure for 15 min followed by resting at atmospheric pressure for 3 h 45 min, and repeating this cycle for up to six times. Microstructural surface analysis of the product under a scanning electron microscope showed an increasingly rigid density of the crystalline structure formed, confirming higher RS3 content

Fundamentals of neurogastroenterology: Basic science

This review examines the fundamentals of neurogastroenterology that may underlie the pathophysiology of functional GI disorders (FGIDs). It was prepared by an invited committee of international experts and represents an abbreviated version of their consensus document that will be published in its entirety in the forthcoming book and online version entitled Rome IV. It emphasizes recent advances in our understanding of the enteric nervous system, sensory physiology underlying pain, and stress signaling pathways. There is also a focus on neuroimmmune signaling and intestinal barrier function, given the recent evidence implicating the microbiome, diet, and mucosal immune activation in FGIDs. Together, these advances provide a host of exciting new targets to identify and treat FGIDs, and new areas for future research into their pathophysiology