Maternal TLR4 and NOD2 Gene Variants, Pro-Inflammatory Phenotype and Susceptibility to Early-Onset Preeclampsia and HELLP Syndrome

Background: Altered maternal inflammatory responses play a role in the development of preeclampsia and the hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome. We examined whether allelic variants of the innate immune receptors toli-like receptor 4 (TLR4) and nucleotide-binding oligomerization domain (NOD2), that impair the inflammatory response to endotexin are related to preeclampsia and HELLP syndrome. Methods and Finding: We determined five common mutations in TLR4 (D299G and T399I and NOD2 (R70W, G908R and L1007fs) in 340 primiparous women with a histo

Proceedings of PVP2005 2005 ASME Pressure Vessels and Piping Division Conference PVP2005-71772 ENPOWER -REPAIR WELDS AND RESIDUAL STRESSES IN CLAD PLATES

ABSTRACT One of the tasks of the European Commission sponsored project ENPOWER was to manufacture repair welds on clad plate specimens simulating the inner wall of a Reactor Pressure Vessel (RPV) and to establish their structural integrity. The paper summarizes the main results from the repair welds carried out on clad plates with an anticipated sub-clad defect including the results from various residual stress measurements and from numerical welding simulations as well as from some fracture mechanical calculations. The results are discussed with respect to support the repair weld optimization in particular by minimizing the residual stresses. Moreover, the application ranges and capabilities of numerical simulations for this kind of weld processes are discussed

Effect of Neutron Flux on an Irradiation-Induced Microstructure and Hardening of Reactor Pressure Vessel Steels

International audienceThe existing knowledge about the effect of neutron irradiation on the mechanical properties of reactor pressure vessel steels under reactor service conditions relies to a large extent on accelerated irradiations realized by exposing steel samples to a higher neutron flux. A deep understanding of flux effects is, therefore, vital for gaining service-relevant insight into the mechanical property degradation. The existing studies on flux effects often suffer from incomplete descriptions of the irradiation-induced microstructure. Our study aims to give a detailed picture of irradiation-induced nanofeatures by applying complementary methods using atom probe tomography, positron annihilation, small-angle neutron scattering and transmission electron microscopy. The characteristics of the irradiation-induced nanofeatures and the dominant factors responsible for the observed increase of Vickers hardness are identified. Microstructural changes due to high flux conditions are smaller nm-sized solute atom clusters with almost the same volume fraction and a higher concentration of vacancies and sub-nm vacancy clusters compared to low flux conditions. The results rationalize why pronounced flux effects on the nanofeatures, in particular on solute atom clusters, only give rise to small or moderate flux effects on hardening

Effect of Neutron Flux on an Irradiation-Induced Microstructure and Hardening of Reactor Pressure Vessel Steels

International audienceThe existing knowledge about the effect of neutron irradiation on the mechanical properties of reactor pressure vessel steels under reactor service conditions relies to a large extent on accelerated irradiations realized by exposing steel samples to a higher neutron flux. A deep understanding of flux effects is, therefore, vital for gaining service-relevant insight into the mechanical property degradation. The existing studies on flux effects often suffer from incomplete descriptions of the irradiation-induced microstructure. Our study aims to give a detailed picture of irradiation-induced nanofeatures by applying complementary methods using atom probe tomography, positron annihilation, small-angle neutron scattering and transmission electron microscopy. The characteristics of the irradiation-induced nanofeatures and the dominant factors responsible for the observed increase of Vickers hardness are identified. Microstructural changes due to high flux conditions are smaller nm-sized solute atom clusters with almost the same volume fraction and a higher concentration of vacancies and sub-nm vacancy clusters compared to low flux conditions. The results rationalize why pronounced flux effects on the nanofeatures, in particular on solute atom clusters, only give rise to small or moderate flux effects on hardening

Towards Safe Long-Term Operation of Reactor Pressure Vessels

This publication summarizes the long term operation (LTO) conditions in European NPPs and provides recommendations on reactor pressure vessel (RPV) irradiation surveillance based on the work performed in the Work Package 7 “Surveillance Guidelines” of the LONGLIFE international project [1]. The LONGLIFE project "Treatment of Long Term Irradiation Embrittlement Effects in RPV Safety Assessment" was 50% funded by the Euratom 7th Framework Programme of the European Commission. The project, coordinated by the Helmholtz-Zentrum Dresden-Rossendorf, successfully finalized in Long2014. Figure 1 shows the different activities carried out by the project partners (16 organizations).JRC.F.5-Nuclear Reactor Safety Assessmen

Monitoring radiation embrittlement during life extension periods

This paper presents guidelines to monitor radiation embrittlement of reactor pressure vessels (RPV) during life extension periods (to 60 or 80 years) or for the long term operation of nuclear power plants (NPP). The guidelines were developed in 2012-2013 by a task group of the international project LONGLIFE. The work performed responds to the need of guidance to treat long term irradiation effects within the ageing management of NPPs, since the standard RPV surveillance programmes were designed only to cover a time period of 40 years. The guidelines intend to support specialists in the field and managers in the plant to choose among the most adequate techniques and methods available today to extend the use of their current RPV surveillance programme beyond design life, or implement a new programme when needed. The study performed identifies weaknesses of the standard surveillance programmes in providing data needed for long term operation, and proposes solutions and tools to solve and/or mitigate the lack or scarcity of surveillance material for their use in life extension. Guidance is also given on methods and strategies to generate reliable surveillance data in the high fluence range.JRC.F.5-Nuclear Reactor Safety Assessmen

Comparison of vaginal and transabdominal collection of amniotic fluid for fetal lung maturity tests

Backgrounds. The lecithin/spingomyelin (L/S) ratio and lamellar body count (LBC) are two tests that can be used to estimate the probability of the occurrence of respiratory distress syndrome (RDS). Our objective was to compare the prognostic capacity of the L/S ratio and the LBC in the prediction of RDS from amniotic fluid that was obtained either transabdominally or vaginally. Methods. Consecutive women undergoing amniotic fluid sampling for determination of fetal lung maturity were included. In case the membranes were ruptured, amniotic fluid was obtained vaginally. Otherwise, amniotic fluid was obtained by transabdominal amniocentesis. In each specimen, an L/S ratio and a LBC were measured. The predictive capacity of specimens that were obtained vaginally and transabdominally were compared by calculating the area under the receiver-operating-characteristic curve (AUC) analysis. Results. In 260 patients amniotic fluid was collected transabominally, whereas in the other 67 patients there were ruptured membranes, and fluid was collected vaginally. RDS occurred in 25% of the patients without ruptured membranes, and in 34% of the patients with ruptured membranes. For the L/S ratio, the AUC was 0.56 (SE 0.09) for the vaginally collected specimens, and 0.93 (SE 0.02) in the specimens that were collected abdominally. For the LBC, the AUCs were 0.52 (SE 0.08) and 0.84 (SE 0.03), respectively. Conclusions. Fetal lung maturity tests that are performed in vaginally obtained specimens in patients with ruptured membranes are of no use in the prediction of RD