bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ageing Management of Dry Storage Systems for Long-Term Storage
Authors: Garcia Justo , Issard Hervé 
Published: November 2014

Nuclear reactors generate used nuclear fuel, which needs to be safely managed. After discharge from operating nuclear reactors, the used nuclear fuel stored during a certain period of time in reactor pool is removed for reprocessing, disposal, or storage elsewhere.
A need for additional storage exists because of delays in used nuclear fuel disposition decisions and the continually increasing volume of used nuclear fuel discharged from reactors. Interim storage of used nuclear fuel is an essential part of the Nuclear Fuel Cycle providing nuclear safety and ensuring protection to the public.
Interim storage of used nuclear fuel currently used includes:
• Dry storage in vaults, casks and containers
• Wet storage, in silos, pools, outside reactor operating areas
Interim dry storage systems were originally designed for limited periods, generally 40–60 years. Interim dry storage is safe as shown by important industrial feedback and the operational records, even from severe accidents.
With extended interim dry storage, technical and safety investigations are presently being carried out concerning used nuclear fuel behavior, and the storage structures and their system components to demonstrate and justify the ability of the systems to store safely and securely the used nuclear fuel for a much longer period of time.
These investigations are part of the ageing management program for the storage system which should address a description of the ageing that could adversely affect structures and components important to safety.
This paper provides highlights of issues related to managing effects on dry cask storage systems for long-term interim storage and transportation of used nuclear fuel.
Development of Inherently Safe Technologies for Large Scale BWRs: (4) Hydrogen Explosion Prevention System Using SiC Fuel Claddings
Authors: Ishibashi Ryo , Ikegawa Tomohiko , Noshita Kenji , Kitou Kazuaki , Kamoshida Mamoru 
Published: November 2014

In the aftermath of the lessons learned from the Fukushima Daiichi nuclear accident, we have been developing the following various safe technologies for boiling water reactors (BWRs), including a passive water-cooling system, an infinite-time air-cooling system, a hydrogen explosion prevention system, and an operation support system for reactor accidents.
One of inherently safe technologies currently under development is a system to prevent hydrogen explosion during severe accidents (SAs). This hydrogen explosion prevention system consists of a high-temperature resistant fuel cladding of silicon carbide (SiC), and a passive autocatalytic recombiner (PAR). Replacing the zircaloy (Zry) claddings currently used in LWRs with the SiC claddings decreases the hydrogen generation and thus decreases the risk of hydrogen leakage from a primary containment vessel (PCV) to a reactor building (R/B) such as an operation floor. The PAR recombines the leaked hydrogen gas so as to maintain the hydrogen concentration at less than the explosion limit of 4 % in the R/B.
The advantages of using SiC claddings in the system were examined through experiments and SA analysis. Results of steam oxidation tests confirmed that SiC was estimated to show 2 to 3 orders of magnitude lower hydrogen generation rates during oxidation in a high temperature steam environment than Zry. Results of SA analysis showed that the total amount of hydrogen generation from fuels was reduced to one fifth or less. Calculation also showed that the lower heat of the oxidation reaction of SiC moderated the steep generation with the temperature increase. We expected this moderated steep generation to reduce the pressure increase in the PCV as well as prevent excess amounts of leaked hydrogen from hydrogen disposal rate capacity using PARs.
The SiC cladding under consideration consists of an inner metallic layer, a SiC/SiC composite substrate, and an outer environment barrier coating (EBC). A thin inner metallic layer in combination with a SiC/SiC composite substrate functions as a barrier for fission products. EBC is introduced to have both corrosion resistance in high temperature water environments during normal operation and oxidation resistance in high temperature steam environments during SA. Further reduction of the hydrogen generation rate in high temperature steam by improving the EBC is expected to decrease the total amount of hydrogen generation even more.
Technical Basis of Fatigue Crack Growth Rate Curve for Ni-Base Alloy in BWR Water Environment
Authors: Ogawa Takuya , Itatani Masao , Saito Toshiyuki , Nagase Hiroshi , Aoike Satoru , Yoneda Hideki 
Published: November 2014

When the flaws are detected in Japanese nuclear power components by in-service inspection, structural integrity assessment are performed in the technical judgment on continuous service. If cyclic loading is assumed, fatigue crack growth analysis should be conducted based on the Rules on Fitness-for-Service for Nuclear Power Plants of the Japan Society of Mechanical Engineers Code (JSME FFS Code). However, fatigue crack growth analysis for BWR components consisting of Ni-base alloy is currently impossible, since the reference curve of fatigue crack growth rate for Ni-base alloy in BWR water environment is not yet prescribed in the JSME FFS Code.
In this study, fatigue crack growth behavior of Ni-base alloy used for Japanese BWR plants in BWR water environment was investigated. Based on the experimental data, the fatigue crack growth rate curve was evaluated. Four test parameters of material, corrosion potential, stress ratio and load rising time were considered. As a result of fatigue crack growth tests, the effects of all test parameters on the fatigue crack growth behavior were found. A Mean curve of fatigue crack growth rate in Paris law format, which was a function of stress ratio and rising time, was formulated based on crack growth data in normal water chemistry (corrosion potential was over 150 mVSHE) for weld metal and heat affected zone (HAZ), respectively. A reference curve of fatigue crack growth rate was also formulated by the statistical treatment considering the scatter of crack growth rate.
Further, in order to determine the threshold stress intensity factor range ΔKth of reference curve of fatigue crack growth, ΔK decreasing tests were conducted under the test condition of 1 second of rising time. As a result, the threshold value of ΔK was evaluated based on the ASTM E 647, and the ΔKth of the reference curve was conservatively determined considering the margin.
Evaluation of Safety Performances of a Superficial Disposal Facility Subject to an Aircraft Impact and Fuel Burning
Authors: Stefanini Lorenzo , Lo Frano Rosa , Bertocchi Fulvio , Forasassi Giuseppe 
Published: November 2014

Safety and security aspects are of meaningful importance in the design of nuclear facilities.
In this study, the attention is so focused on the potential damaging effects that a large civilian airplane impact could bring in safety relevant structures, like a superficial repository similar to El Cabril one.
Safety performances of such a type of superficial disposal facility, subjected to the aircraft impact and fuel burning, have been analysed and discussed.
Conservative assumptions have been made: normal impact on the lateral repository surface, fire scenario based on the amount of fuel burnt.
Load functions (calculated with the Riera approach) and the maximum temperature reached by fuel during its combustion were used as input (boundary condition) in the numerical simulations as well as the damaging phenomena occurring in the concrete structure.
Numerical analyses, by MARC© code, allowed to simulate the thermo-structural performances of the superficial repository.
The obtained results showed that a repository wall thickness, ranging from 0.6 to 0.9 m, is not sufficient to prevent the penetration of wall itself. Despite the ongoing concrete degradation phenomena, the global strength of the repository seemed to be guaranteed.
Horizontal Drop Test Evaluation of a Packaging System
Authors: Sanfiorenzo Antonio , Lo Frano Rosa , Pugliese Giovanni , Forasassi Giuseppe 
Published: November 2014

In the transportation of radioactive waste, the package is designed as the major engineered system capable to ensure the containment and provide safety functions, such as radiation shielding, structural integrity against external mechanical and thermal loads, dissipation of the decay heat, etc. Packaging systems are designed in accordance to rigorous acceptance requirements, like the International Atomic Energy Agency (IAEA) ones, so to provide protection to human being and environment against radiation exposure and contamination, particularly in reference accident scenarios including, as it is widely known in literature, drop, puncture, fire and submersion tests. The scope of the present study is to evaluate the structural response and performance in a free drop test condition of a new Italian packaging system that should be used for the transportation of low and intermediate level radioactive wastes. For this purpose the carried out numerical analyses are presented and discussed. The numerical analyses, performed by the finite element MARC® code, simulate the behaviour of the packaging system components: the overpack, gasket, cover lid, bolts and a concrete matrix representative of the radioactive content.
The obtained results for 1.2 m horizontal drop, on a flat and unyielding surface, were critically analysed and also compared to the experimental ones obtained from the experimental test campaign performed at the Unipi test facility on the new Italian packaging system considered.
The stress and acceleration values indicate that the package, although rather local deformations in correspondence of bolts and secondary lid, is capable to withstand the dynamic loading generated during the drop test without any unacceptable loss of the safety features.
Developing Structural Design Criteria for Fusion Reactor In-Vessel Components
Authors: Kalsey M. , Porton M. 
Published: November 2014

Co-ordinated international activities are underway to complete an EU fusion demonstration power plant conceptual design by 2020, for construction in the early 2030s. However, many engineering design challenges still remain. For example, the design of in vessel components is technically challenging, with many design constraints needing to be mutually satisfied. One of the key challenges is the design validation of in-vessel structural components operating within the unique fusion environmental conditions. It has been recognized that these components would benefit from design criteria that have been specifically developed, providing improved accuracy and appropriate conservatism. This would provide DEMO designers with a much needed increase in design space and guidance.
This paper highlights the justification behind developing fusion specific structural design criteria, discusses the key technical gaps of existing criteria and elaborates on the need to develop non-technical aspects of the documentation including consideration of human factors in design validation. Finally, a structured design criteria development plan is presented, highlighting planning work by the European fusion community to address these gaps in step with the current design milestones for the realisation of an EU DEMO.
Simulation of PWR Crud
Authors: Byers W. A. , Wang G. , Young M. Y. , Deshon J. 
Published: November 2014

Corrosion products deposit on Pressurized Water Reactor (PWR) fuel rod cladding surfaces and can create a number of issues including increased cladding temperature, elevated cladding corrosion, and the precipitation of boron species within the deposits. The deposits can also release and lead to increased radiation fields on system ex-core surfaces. These effects can vary widely from plant-to-plant. The amount of the deposits, commonly known as crud, is an important factor in determining the impact, but other parameters such as crud thickness, porosity, and composition are also thought to be important.
The Electric Power Research Institute (EPRI) has sponsored a number of programs to better understand the characteristics of crud and its effects. Crud has been sampled by fuel scraping and by collecting suspended crud during operation and during fuel cleaning. The chemistry and structure of the crud was then characterized. These data were then used to create simulated crud in laboratory heated rod tests. These tests explored how the crud deposits affected heat transfer at the rod surface and the interaction between the crud and the simulated coolant.
This paper discusses the nature of PWR crud and some of the practical aspects of crud simulation. Different approaches to laboratory crud creation will be reviewed, and the success in matching plant crud characteristics will be shown, with special emphasis on the production of crud for thermal conductivity measurement.
Autotransporter-Based Antigen Display in Bacterial Ghosts
Authors: Hjelm Anna , Söderström Bill , Vikström David , Jong Wouter S. P. , Luirink Joen , de Gier Jan-Willem 
Published: November 2014

ABSTRACT

Bacterial ghosts are empty cell envelopes of Gram-negative bacteria that can be used as vehicles for antigen delivery. Ghosts are generated by releasing the bacterial cytoplasmic contents through a channel in the cell envelope that is created by the controlled production of the bacteriophage ϕX174 lysis protein E. While ghosts possess all the immunostimulatory surface properties of the original host strain, they do not pose any of the infectious threats associated with live vaccines. Recently, we have engineered the
Escherichia coli
autotransporter hemoglobin protease (Hbp) into a platform for the efficient surface display of heterologous proteins in Gram-negative bacteria, HbpD. Using the
Mycobacterium tuberculosis
vaccine target ESAT6 (early secreted antigenic target of 6 kDa), we have explored the application of HbpD to decorate
E. coli
and
Salmonella
ghosts with antigens. The use of different promoter systems enabled the concerted production of HbpD-ESAT6 and lysis protein E. Ghost formation was monitored by determining lysis efficiency based on CFU, the localization of a set of cellular markers, fluorescence microscopy, flow cytometry, and electron microscopy. Hbp-mediated surface display of ESAT6 was monitored using a combination of a protease accessibility assay, fluorescence microscopy, flow cytometry and (immuno-)electron microscopy. Here, we show that the concerted production of HbpD and lysis protein E in
E. coli
and
Salmonella
can be used to produce ghosts that efficiently display antigens on their surface. This system holds promise for the development of safe and cost-effective vaccines with optimal intrinsic adjuvant activity and exposure of heterologous antigens to the immune system.
New Multilocus Variable-Number Tandem-Repeat Analysis Tool for Surveillance and Local Epidemiology of Bacterial Leaf Blight and Bacterial Leaf Streak of Rice Caused by Xanthomonas oryzae
Authors: Poulin L. , Grygiel P. , Magne M. , Gagnevin L. , Rodriguez-R L. M. , Forero Serna N. , Zhao S. , El Rafii M. , Dao S. , Tekete C. , Wonni I. , Koita O. , Pruvost O. , Verdier V. , Vernière C. , Koebnik R. 
Published: November 2014

ABSTRACT

Multilocus variable-number tandem-repeat analysis (MLVA) is efficient for routine typing and for investigating the genetic structures of natural microbial populations. Two distinct pathovars of
Xanthomonas oryzae
can cause significant crop losses in tropical and temperate rice-growing countries. Bacterial leaf streak is caused by
X. oryzae
pv. oryzicola, and bacterial leaf blight is caused by
X. oryzae
pv. oryzae. For the latter, two genetic lineages have been described in the literature. We developed a universal MLVA typing tool both for the identification of the three
X. oryzae
genetic lineages and for epidemiological analyses. Sixteen candidate variable-number tandem-repeat (VNTR) loci were selected according to their presence and polymorphism in 10 draft or complete genome sequences of the three
X. oryzae
lineages and by VNTR sequencing of a subset of loci of interest in 20 strains per lineage. The MLVA-16 scheme was then applied to 338 strains of
X. oryzae
representing different pathovars and geographical locations. Linkage disequilibrium between MLVA loci was calculated by index association on different scales, and the 16 loci showed linear Mantel correlation with MLSA data on 56
X. oryzae
strains, suggesting that they provide a good phylogenetic signal. Furthermore, analyses of sets of strains for different lineages indicated the possibility of using the scheme for deeper epidemiological investigation on small spatial scales.
Dynamics of the Establishment of Multinucleate Compartments in Fusarium oxysporum
Authors: Shahi Shermineh , Beerens Bas , Manders Erik M. M. , Rep Martijn 
Published: November 2014

ABSTRACT

Nuclear dynamics can vary widely between fungal species and between stages of development of fungal colonies. Here we compared nuclear dynamics and mitotic patterns between germlings and mature hyphae in
Fusarium oxysporum
. Using fluorescently labeled nuclei and live-cell imaging, we show that
F. oxysporum
is subject to a developmental transition from a uninucleate to a multinucleate state after completion of colony initiation. We observed a special type of hypha that exhibits a higher growth rate, possibly acting as a nutrient scout. The higher growth rate is associated with a higher nuclear count and mitotic waves involving 2 to 6 nuclei in the apical compartment. Further, we found that dormant nuclei of intercalary compartments can reenter the mitotic cycle, resulting in multinucleate compartments with up to 18 nuclei in a single compartment.
Spectrum of patients intentionally poisoned with an emulsified concentrate pendimethalin herbicide
Authors: Moon Jeongmi , Chun Byeongjo 
Published: November 2014

ObjectiveStudies on the acute toxicity of pendimethalin herbicide in humans are limited. Therefore, this study investigated the clinical characteristics of acute intentional pendimethalin herbicide poisoning.Material and methodA retrospective observational case series was conducted involving 17 patients with a history of intentional pendimethalin herbicide ingestion. Data were collected on clinical manifestations, management and final outcome.ResultThe mortality rate was 0%; however, four patients (23.5%) exhibited metabolic acidosis, hypotension or respiratory failure within the first 24 h after ingestion and required admission to the intensive care unit. The most common complication was respiratory failure, followed by hypotension. Complicated patients tended to show an altered mental state and X-ray abnormalities at presentation.Discussion and conclusionsPhysicians should be aware that patients who have been poisoned with pendimethalin herbicide, and particularly patients with a depressed mental state and X-ray abnormalities at presentation, may exhibit metabolic acidosis, hypotension, respiratory failure or pancreatitis.
KIT genetic alterations in anorectal melanomas
Authors: Santi Raffaella , Simi Lisa , Fucci Rossella , Paglierani Milena , Pepi Monica , Pinzani Pamela , Merelli Barbara , Santucci Marco , Botti Gerardo , Urso Carmelo , Massi Daniela 
Published: November 2014

BackgroundMucosal melanomas (MM) represent a heterogeneous tumour population that exhibits site-specific molecular profiles.AimsIn a multicentre retrospective study, we investigatedKITaberrations in primary anorectal (AR) melanomas compared with melanoma metastatic to the gastrointestinal (GI) tract.MethodsPrimary AR MM (n=31) and GI metastatic melanoma (n=27) were studied forKITmutations on exons 11, 13, 17 and 18 by high-resolution melting analysis, direct sequencing and c-KIT expression by immunohistochemistry. Selected cases were also investigated for increasedKITgene copy number by fluorescent in situ hybridisation.ResultsFunctionalKITmutations were demonstrated in 11/31 (35.5%) of AR melanomas and in 1/26 (3.8%) of GI melanoma metastases (p=0.004). A significant difference emerged between primary and metastatic MM with regards to KIT-positive immunostaining (p=0.002). Immunohistochemical c-KITprotein overexpression did not correlate withKITmutational status. IncreasedKITcopy number was demonstrated in 5/20 AR primary cases.ConclusionsThe rate of functional mutations inKITis significantly higher in AR MM than in GI metastatic melanoma. KIT protein overexpression does not correlate withKITmutations and cannot be used for screening purposes. Recognising the molecular heterogeneity of MM helps to identify patients who require a different therapeutic approach.
Gas-breakthrough pressure of FEBEX bentonite
Authors: Gutiérrez-Rodrigo Vanesa , Villar María Victoria , Martín Pedro Luis , Romero Francisco Javier , Barcala José Miguel 
Published: November 2014

Abstract
The gas-breakthrough pressure values in saturated FEBEX bentonite were determined for different dry densities and sample sizes. They increased clearly with dry density and were always higher than the swelling pressure of the bentonite. In high-density samples, gas flow tended to stop abruptly after breakthrough, whereas, in lower density samples, gas flow decreased gradually until a given pressure gradient was reached. The permeabilities computed after breakthrough (which usually did not stabilize) were inversely related to dry density. This would indicate that, despite the fact that flow took place through preferential pathways, the bentonite matrix and its swelling conditioned the ease of pathway formation. These paths sometimes closed quickly after breakthrough and others remained open, allowing a gradual decrease in gas flow. After resaturation of the bentonite, the same breakthrough pressures and permeabilities were found, pointing to the perfect healing of these preferential pathways. A sealed interface along the bentonite did not seem to affect the breakthrough pressure or permeability values.