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Summary: Optimization of nuclear fuel cycles is essential for experts and policy makers for studying and analyzing the future of the nuclear energy. In the case of advanced electronuclear transition scenarios, multiple parameters with a complex dependence have to be fine‐tuned in order to achieve a set of predefined objectives. However, in the presence of uncertainties the solutions obtained in this way may not be stable since small perturbations could break the delicate balance between different parts of the scenario. In this work, the optimization of an uncertainty European‐based sustainable transition scenario has been studied. This scenario, which has been analyzed with the TR_EVOL nuclear fuel cycle simulator system, is aimed at reducing the transuranic inventory masses while keeping the fuel cycle costs. To that end, an extension of the DEMO evolutionary multiobjective algorithm has been implemented within TR_EVOL for allowing the inclusion of constraints and uncertainties with a methodology that can be used by any fuel cycle simulator. Results show the importance of coupling optimization and uncertainty analyses due to the suboptimal and unstable solutions that can be obtained if not considered jointly. In addition, the uncertainties shrink the decision space. It was found that in their presence the transuranic mass can be reduced and stabilized by a factor ranging between 65% and 71% with an increase of the cost of 16% and 18.5% after 300 years of operation by using advanced systems when compared with an open fuel cycle strategy. [ABSTRACT FROM AUTHOR]

Highlights • The prompt method and the 1/v insertion method have been implemented in SUMMON. • Methods to derive the sensitivity to nuclear data of β eff and Λ eff are presented. • The sensitivity methods have been verified against well-validated codes. • Good agreement between SUMMON and SUSD3D and SERPENT has been obtained. Abstract Accurate and reliable tools for sensitivity analysis and uncertainty quantification are needed to estimate the uncertainties in reactor key parameters (k eff , β eff , Λ eff , safety coefficients, ...) and to identify possible nuclear data weaknesses. A Sensitivity and Uncertainty Methodology for MONte carlo codes (SUMMON) has been developed to calculate the sensitivities of the criticality safety parameters as well as their uncertainties due to uncertainties in nuclear data, addressing limitations of existing tools. The methodology is currently based on the use of the KSEN card of MCNP6 code to perform the eigenvalue sensitivity calculations, although any Monte Carlo code that can provide sensitivity coefficients can be used. The sensitivity coefficients of a reactivity response are calculated using the eigenvalue definition of reactivity, which is equivalent to applying the Equivalent Generalized Perturbation Theory. Moreover, the effective delayed neutron fraction sensitivity coefficients are derived from Bretscher's approximation, whereas the sensitivity coefficients of the effective neutron generation time are obtained using the 1/v insertion method and the Equivalent Generalized Perturbation Theory. Uncertainties are propagated using the "Sandwich Rule" of the "Propagation of Moments" method employing state-of-the-art covariance libraries. The implementation in SUMMON of Bretscher's approximation and the 1/v insertion method has been validated using integral experiments from ICSBEP and IRPhE databases, while the methods for calculating the sensitivity coefficients have been verified against consolidated codes, such as SCALE, SUSD3D, SERPENT and XSUSA and good agreement has been obtained. [ABSTRACT FROM AUTHOR]

Highlights • Possibility of waste minimization and stabilization of transuranic inventories. • Complementarity of local and global methods for uncertainty quantification. • Few input parameters impact on the uncertainty of plutonium and minor actinides masses. • Lineal dependence on input parameters. Abstract A European fuel cycle scenario based on PATEROS where the minimization and the posterior stabilization of the TRU inventory is the main goal, has been studied in terms of uncertainty propagation of the input parameters with the fuel cycle transition scenario TR_EVOL code. Local and global sensitivity methods (namely sensitivity coefficients and Sobol decomposition of variance) were used in a complementary way in order to overcome the limitations of each technique. Those parameters with the largest impact in terms of uncertainty quantification are presented for the most relevant outputs in this kind of scenarios. It was found that the UOX thermal efficiency is the variable with the highest impact in the Pu stocks, while for the MA stocks the isotopic composition of the ADS fuel plays the relevant role. Neither significant interactions nor high order effects were found over the selected input parameters, indicating that for this scenario, the response model can be approximated by a multivariable linear function. [ABSTRACT FROM AUTHOR]

Highlights • An injectable new prodrug was tested against immature and adult flukes. • The experimental compound exerts high efficacy against adults. • The new injectable fasciolicide used half the dose of the oral parent compound. • The solubilized alpha prodrug might reduce environmental contamination. Abstract The effective dose of an injectable prodrug, named compound alpha prodrug, against immature and adult Fasciola hepatica in experimentally infected sheep was determined. In a first experiment, 30 sheep were infected with Fasciola hepatica on day 0 and 50. After microscopic detection of faecal eggs on day 80, groups (n = 6) 1 to 3 were treated with 6, 8 and 10 mg/kg of the experimental water-soluble prodrug compound alpha intramuscularly, respectively. Group 4 was treated with closantel and group 5 remained untreated. Copromicroscopical examinations were made on day 0, 80 and 108. On day 110, trematodes were collected from the bile ducts. Fasciolicide efficacy was assessed as a percentage of fluke-egg and adult-fluke reduction. Fluke length was also recorded. In a second experiment aimed to assess the fasciolicide activity of compound alpha prodrug against four-week-old flukes, 12 sheep were infected on day 0 and allocated into two groups (n = 6). On day 50 post infection, group A was treated with the experimental water-soluble prodrug compound alpha at 6 mg/kg/IM and B remained untreated. Fasciolicide activity was assessed on day 80 after collection, microscopic observation and measurement of flukes present in the parenchyma for immature stages and on day 108 for adults. Egg output decreased 91.2, 96.0, 98.8 and 94.9% for groups 1, 2, 3 and 4, respectively. Compound alpha prodrug cleared 97.6%, 98.51% and 100% of adult stages in a dose-dependent manner. Closantel killed 81.95% flukes. Regarding the second experiment, 81.2% efficacy was achieved. Immature flukes were significantly smaller in the treated group. It is concluded that the intramuscular application of compound alpha prodrug exerted fasciolicide efficacy against adults of Fasciola hepatica. [ABSTRACT FROM AUTHOR]

We have measured with a LaCl 3 detector the γ -ray spectrum emitted by a 235 U enriched UO 2 fuel rod 10 s after being irradiated with thermal neutrons. The experimental results are compared with simulations performed with the fission product yield and radioactive decay data libraries present in the most recent releases of ENDF/B, JEFF and JENDL. [ABSTRACT FROM AUTHOR]

A sensitivity and uncertainty analysis was carried out to estimate the uncertainty in the neutron multiplication factor k eff and to identify the most important nuclear data for neutron induced reactions for criticality calculations of the latest MYRRHA designs. Sensitivity profiles, i.e. sensitivity to the nuclear data as a function of incoming neutron energy, were derived for both a critical and sub-critical core. They were calculated using codes that are based on different methodologies including stochastic and deterministic calculations (i.e. SCALE, MCNP and XSUN). The neutron induced nuclear data sensitivity analysis outlined the following quantities to be of special importance for the MYRRHA reactor concept: 239 Pu(n,γ) both in resonance and fast energy region, (n,f) fast, χ and ν fast; 238 U(n,n′) fast, (n,γ) resonance and fast, (n,n) resonance and fast; 240 Pu ν fast; 238 Pu(n,f) both resonance and fast; 56 Fe(n,γ) both resonance and fast. Differences of less than 4% between codes were obtained for these quantities, with few exceptions ( 238 Pu(n,f), 238 U(n,n) and 56 Fe(n,γ) reactions). Nuclear data covariance matrices of different libraries (SCALE-6, COMMARA-2 and JENDL-4.0m) were used to derive the uncertainty in k eff based on the calculated sensitivities. This study reveals that the largest contributions to k eff uncertainty result from the uncertainty in the average prompt neutron fission multiplicity of 239 Pu, in the 238 U inelastic scattering cross section and 239 Pu fission cross section, using the covariances from SCALE-6, COMMARA-2 and JENDL-4.0m, respectively. [ABSTRACT FROM AUTHOR]

Burn-up calculations with the MCNP code are based on the cinder.dat library, which includes the information of the cross-sections, the fission product yields and the decay data necessary to perform the depletion (among others). This library is based mainly on ENDF/B-VI.0 and has been enhanced with other databases, but no version based on other libraries (like JEFF or JENDL) is available in the bibliography or supplied with the MCNP code. This creates an inconsistency when other libraries are used for transport since the information of different libraries is mixed in the burn-up process. This study aims to evaluate the impact of the use of the cinder.dat library when other libraries are desired for transport and of the full replacement of the library file. In this paper, a new library has been developed and proposed to replace cinder.dat when coherent calculations using JEFF-3.3 for transport and burn-up are desired. • MCNP/CINDER and EVOLCODE successful validation. • Study of the impact of cinder.dat library in MCNP/CINDER calculations. • Creation of a new cinder.dat-JEFF-3.3 library for coherent burn-up calculations with MCNP. [ABSTRACT FROM AUTHOR]

Abstract: The design of Accelerator Driven Systems (ADS) requires the development of simulation tools that are able to describe in a realistic way their nuclear performance and transmutation rate capability. In this publication, we present an evaluation of state of the art Monte Carlo design tools to assess their performance concerning transmutation of long-lived fission products. This work, performed under the umbrella of the International Atomic Energy Agency, analyses two important aspects for transmutation systems: moderation on Lead and neutron captures of 99Tc, 127I and 129I. The analysis of the results shows how shielding effects due to the resonances at epithermal energies of these nuclides affects strongly their transmutation rate. The results suggest that some research effort should be undertaken to improve the quality of Iodine nuclear data at epithermal and fast neutron energy to obtain a reliable transmutation estimation. [Copyright &y& Elsevier]

A fast numerical method for the calculation in a zero-dimensional approach of the equilibrium isotopic composition of an iteratively used transmutation system in an advanced fuel cycle, based on the Banach fixed point theorem, is described in this paper. The method divides the fuel cycle in successive stages: fuel fabrication, storage, irradiation inside the transmutation system, cooling, reprocessing, and incorporation of the external material into the new fresh fuel. The change of the fuel isotopic composition, represented by an isotope vector, is described in a matrix formulation. The resulting matrix equations are solved using direct methods with arbitrary precision arithmetic. The method has been successfully applied to a double-strata fuel cycle with light water reactors and accelerator-driven subcritical systems. After comparison to the results of the EVOLCODE 2.0 burn-up code, the observed differences are about a few percents in the mass estimations of the main actinides. [ABSTRACT FROM AUTHOR]

In cattle, Eimeria produces clinical disease with different degrees of severity, depending on the dominant species. Eimeria bovis triggers severe intestinal damage, while E. alabamensis causes minimal damage. Cytokines and other factors derived from epithelial cells play important roles in inflammatory and immune responses in intestinal tissue. This study aimed to obtain a detailed view of IFN-γ and IL-4 mRNA expression as well as of activation of NF-κB p50 and p65 subunits induced by E. bovis or E. alabamensis in intestinal epithelial cells by means of a RT-PCR assay and a NF-κB p50/p65 ELISA-based kit, respectively. Our results demonstrate that infection by both Eimeria species enhances IL-4 mRNA expression in intestinal cells. However, IL-4 was expressed more intensely in cells incubated with E. bovis whereas IFN-γ levels were higher and detected at an earlier time in cells infected with E. alabamensis. NF-κB was activated in infected cells irrespective of species, yet the activity of the p50 subunit was significantly higher in cells incubated with E. bovis. Our results suggest that the intensity of host-cell responses triggered by these two Eimeria species could be considered as potential determinants of pathogenicity. [ABSTRACT FROM AUTHOR]

Avian embryos at high altitude do not benefit of the maternal protection against hypoxia as in mammals. Nevertheless, avian embryos are known to hatch successfully at altitudes between 4000 and 6500 m. This review considers some of the processes that bring about the outstanding modifications in the pressure differences between the environment and mitochondria of avian embryos in hypoxic environments. Among species, some maintain normal levels of oxygen consumption (&Vdot;O2) have a high oxygen carrying capacity, lower the air cell-arterial pressure difference (PAO2-PaO2) with a constant pH. Other species decrease &Vdot;O2, increase only slightly the oxygen carrying capacity, have a higher PAO2-PaO2 difference than sea-level embryos and lower the PCO2 and pH. High altitude embryos, and those exposed to hypoxia have an accelerated decline of erythrocyte ATP levels during development and an earlier stimulation of 2,3-BPG synthesis. A higher Bohr effect may ensure high tissue PO2 in the presence of the high-affinity hemoglobin. Independently of the strategy used, they serve together to promote suitable rates of development and successful hatching of high altitude birds in hypoxic environments. [Copyright &y& Elsevier]

Presents a study which explored the relationship of ovarian hormones to hypoxemia in women. Materials and methods used in the study; Results; Discussion.

Studies the relationship of ovarian hormones to hypoxemia in post and premenopausal women residing at 4,300 meters above sea level in Spain. Level of erythrocytosis in women with chronic mountain sickness; Comparison of estradiol and progesterone levels during the luteal and follicular phases.

Focuses on a study which evaluated the mechanisms involved in norepinephrine (NE)-induced desensitization of the adrenergic receptor pathway in male Wistar rats. Materials and methods of the study; Physiological data; Density, affinity and distribution of cardiac adrenoceptors; Description of adenylate cyclase activity.

Examines the mechanisms involved in the norepinephrine (NE)-induced desensitization of the cardiac adrenergic receptor pathway in male Wistar rats. Hypertrophic response of hypoxia and NE; Functional activities of G proteins in cardiac membranes; Role of pertussis toxin in abolishing the decrease in isoproterenol-stimulated activity in the left ventricle.

The 246 Cm(n, γ ) and 248 Cm(n, γ ) cross-sections have been measured at the Experimental Area 2 (EAR2) of the n_TOF facility at CERN with three C 6 D 6 detectors. This measurement is part of a collective effort to improve the capture cross-section data for Minor Actinides (MAs), which are required to estimate the production and transmutation rates of these isotopes in light water reactors and innovative reactor systems. In particular, the neutron capture in 246 Cm and 248 Cm open the path for the formation of other Cm isotopes and heavier elements such as Bk and Cf and the knowledge of (n, γ ) cross-sections of these Cm isotopes plays an important role in the transport, transmutation and storage of the spent nuclear fuel. The reactions 246 Cm(n, γ ) and 248 Cm(n, γ ) have been the two first capture measurements analyzed at n_TOF EAR2. Until this experiment and two recent measurements performed at J-PARC, there was only one set of data of the capture cross-sections of 246 Cm and 248 Cm, that was obtained in 1969 in an underground nuclear explosion experiment. In the measurement at n_TOF a total of 13 resonances of 246 Cm between 4 and 400 eV and 5 of 248 Cm between 7 and 100 eV have been identified and fitted. The radiative kernels obtained for 246 Cm are compatible with JENDL-5, but some of them are not with JENDL-4, which has been adopted by JEFF-3.3 and ENDF/B-VIII.0. The radiative kernels obtained for the first three 248 Cm resonances are compatible with JENDL-5, however, the other two are not compatible with any other evaluation and are 20 and 60% larger than JENDL-5. [ABSTRACT FROM AUTHOR]

• A target accuracy assessment has been performed with the state-of-the-art JEFF-3.3 and ENDF/B-VIII.0 nuclear data libraries. Target accuracies in k eff and change in coolant density responses for both MYRRHA and ESFR reactors are exceeded. • Nuclear data needs in JEFF-3.3 and ENDF/B-VIII.0 for MYRRHA and ESFR design optimization have been identified. • Data assimilation with JEFF-3.3 has been carried out using individual experiments from ICSBEP and IRPhE databases. • Total uncertainties are strongly reduced and target accuracy for the coolant density expansion coefficient are met after the adjustment. Sodium-cooled Fast Reactors and Lead-cooled Fast Reactors have been selected by the Sustainable Nuclear Energy Technology Platform as technologies that can meet future European energy needs. To achieve the requested level of safety for these reactor technologies and to minimize the increase in the costs due to additional safety measures, accurate and reliable nuclear data are necessary. The objective of this work has been to analyse and improve the nuclear data required for the development, safety assessment and licensing of SFRs and LFRs, reducing the uncertainties in the reactor integral responses due to the uncertainties in nuclear data, in order to reach the target accuracies defined by researchers, industry and regulators. To that end, target accuracy and data assimilation analyses have been performed to identify nuclear data weaknesses and to reduce the uncertainties of integral safety-related parameters due to neutron induced nuclear data. As a result of this work, nuclear data needs for advanced SFRs and LFRs have been identified, improvements of existing nuclear data libraries have been suggested, nuclear data have been adjusted and uncertainties in reactor integral parameters have been reduced, meeting target accuracies after adjustment. [ABSTRACT FROM AUTHOR]

• Sparse Polynomial Chaos expansion methodology applied to an advanced fuel cycle. • Estimation of the Sobol indices and high degree interactions. • Large reduction of the computational requirements for sensitivity analyses. • Methodology applicable by any institution using any fuel cycle code. Uncertainty and sensitivity analyses are required in fuel cycle analyses for studying the viability of electronuclear scenarios by means of their response to variations in the input parameters. This implies that nuclear fuel cycle simulators have to be extended for dealing with this kind of problems in order to become reliable tools. However, given their complexity, the excessive computational effort these analyses demand constraint the ability of the codes to solve the problem without making any approximation. In this work, we propose to use a methodology based on a sparse Polynomial Chaos expansion that, given the low computational demand, makes it possible to be used for sensitivity analyses in any fuel cycle code. This has been applied to a European collaborative advanced scenario where the results have been compared with previous studies with the aim of showing the potential that this technique has when applied to fuel cycle studies. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is the most frequent joint disease worldwide with yet no known disease modifying drugs. In OA chondrocytes (OAC), the dysregulation of the metabolic biosensors that control mitochondrial biogenesis accounts for decreased numbers of mitochondria (MT) and reduced ATP levels in OA. Recently, our group evidenced that natural and artificial MT transfer (MitoT) from MSCs, convey potent metabolic and functional effects on target T cells, controlling organ damage and survival in an in-vivo model of inflammatory disease. In the present work, the effects of MitoT on the OAC phenotype is assessed in a coculture of MT-labelled MSCs with OAC. MitoT was evidenced as early as 4hrs and reached 97% after 24 hours. Cytochalasin B inhibition pointed to a tunneling Nanotubes (TNT)-dependent mechanism. The impact of MitoT, isolated from other effects of the MSC secretome was assessed in OACs incubated solely with MSC derived MT. FACS analysis revealed the internalization of exogenous MT with dose-dependent uptakes of MT equivalent to MSC:OAC ratios of 1:10, 1:5 and 1:1, with averages of 20.1%, 29.4% and 91.7% MitoTpos target OACs, respectively. Functional effect of the MitoT was assessed in readouts including (a) immunosuppression assays, where MitoTpos OAC induced only a slight change in PBMCs proliferation; (b) metabolic activity measured by WST-1 demonstrating an increase in the metabolic activity of MitoTpos OACs; (c) ROS-regulating autophagy gene expression levels showing a significant increase in SOD2 and Redd1mRNA levels in MitoTpos cells and (d) resistance to oxidative stress, assessed following H 2 O 2 treatment, that revealed a protective effect of MitoT (15% reduction of dead cells). Furthermore, the intracellular fate of donated MT was evaluated with MT specific SNPs from the D-loop region. Using the amplification refractory mutation system (ARMS), a unique PCR product for MSC-derived MT was identified for at least 9 days in the target OACs. In conclusion, OAC were shown to be highly permissive for MT donation. The MitoT effect included an increase of metabolic activity and oxidative stress resistance that was correlated with an upregulation of SOD-2 expression. The biodistribution and efficacy of intraarticular injection of MT are currently being investigated in an OA mouse model. The MitoT induced reversal of the metabolic dysfunction typical of OACs might open new avenues to the understanding and treatment of OA. [ABSTRACT FROM AUTHOR]

The advancement of the design of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED) beyond the conceptual phase, passes through the analysis of the impact of uncertainties, notably to what concerns safety-related conditions. Compliancy of plant safety to Design Extension Conditions is, according to IAEA and in line with the meaning itself of these beyond-design conditions, usually investigated by best estimates only. Due however to the demonstration nature of ALFRED, it was decided to assess the actual safety performances of this system even in ultimate conditions. To this regard, the emphasis was put on unprotected events like the UTOP (unprotected transient of over-power) and ULOOP (unprotected loss of offsite power, resulting from the combination of a loss of flow and loss of heat sink under unprotected conditions), pinpointed as the most challenging situations sought for the plant. The purpose of the present work, which has been divided in three parts, was then to assess the ultimate ALFRED safety margins against failure of the key core components and systems (Part III). To target this objective, the evaluation of uncertainties coming, on one hand, from nuclear data was performed at first, to retrieve their impact on the reactivity coefficients, thereby on the transient behavior driven by the latter (Part I); then, uncertainties from material properties, fabrication procedures, operation and computational tools were propagated to assess their influence on the thermal-hydraulics of the system (Part II). In this work the focus is on the latter uncertainties. The adopted methodology is presented at first, namely the semi-statistical vertical approach – characterized by an optimal degree of conservatism among the classical approaches – targeting a 3σ confidence interval. Then, the identification and propagation of each effect are shown, by means of the heat equations, so to retrieve the actual uncertainties on the parameters of interest (the temperatures themselves). Finally, a hot spot analysis to quantify the uncertainty-distorted temperature field is elaborated and presented. The performed analysis has revealed the great impact of fabrication tolerances for the coolant, film and clad temperature rises, particularly affecting safety margins during an ULOOP, while models and material properties uncertainties seem to dominate for the gap and fuel rises, which concur notably in challenging the respect of the fuel melting limit in an UTOP. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the acute and subacute toxicity of the injectable alpha compound to Hsd Han: WIST rats. For the acute toxicity assessment, rats were inoculated with doses of 2 000, 1 000, 500, 100, or 10 mg/kg alpha compound intramuscularly. The results of histopathological analysis did not show apparent changes with the doses used. Notably, 2 animals died after treatment with the 2 000 mg/kg dose, and one animal died in the 1 000 mg/kg group. In the subacute toxicity study, neither male nor female rats inoculated with repeated doses of 8, 24, and 40 mg/kg alpha compound showed significant changes in percent body weight (P = 0.5930). Among the females, significant differences were observed for the serum biochemical parameters glucose and cholesterol in the group inoculated with 8 mg/kg compared to the control. The hematocrit values in the 8, 24 and 40 mg/kg groups and the platelet count in the 24 mg/kg group were significantly different (P = 0.0110) among the females compared to the control group. For the male rats, significant differences were found in erythrocyte count and mean corpuscular volume (MCV) in the groups treated with 8 and 40 mg/kg. However, these values are normal according to the literature. The histopathological evaluations did not show apparent changes, so it is concluded that the alpha compound has a wide margin of safety after injection. [ABSTRACT FROM AUTHOR]

While nucleation may represent one of the major processes responsible for the total aerosol number burden in the atmosphere, and especially at high altitude, new particle formation (NPF) events occurring in the upper part of the troposphere are poorly documented in the literature, particularly in the southern hemisphere. NPF events were detected and analyzed at the highest measurement site in the world, Chacaltaya (5240 m a.s.l.), Bolivia between January 1 and December 31 2012, using a Neutral Aerosol and Ion Spectrometer (NAIS) that detects clusters down to 0.4 nm. NPF frequency at Chacaltaya is one of the highest reported so far (63.9%) and shows a clear seasonal dependency with maximum up to 100% during the dry season. This high seasonality of the NPF events frequency was found to be likely linked to the presence of clouds in the vicinity of the station during the wet season. Multiple NPF events are seen on almost 50% of event days and can reach up to 6 events per day, increasing the potential of nucleation to be the major contributor to the particle number concentrations in the upper troposphere. Ion-induced nucleation (IIN) was 14.8% on average, which is higher than the IIN fractions reported for boundary layer stations. The median formation rate of 2 nm particles computed for first position events is increased during the dry season (1.90 cm −3 s −1 ) compared to the wet season (1.02 cm − 3 s −1 ), showing that events are more intense, on top of being more frequent during the dry season. On the contrary, particle growth rates (GRs) are on average enhanced during the wet season, which could be explained by higher amount of biogenic volatile organic compounds transported from the Amazon rainforest. The NPF events frequency is clearly enhanced when air masses originate from the oceanic sector, with a frequency of occurrence close to 1. However, based on the particle GRs, we calculate that particles most likely nucleate after the oceanic air masses reach the land and are presumably not originating from the marine free troposphere. The high frequency of NPF events, the occurrence of multiple events per day, and the relatively high formation rates observed at Chacaltaya imply that nucleation and growth are likely to be the major mechanism feeding the upper atmosphere with aerosol particles in this part of the continent. [ABSTRACT FROM AUTHOR]

Abstract: Minor actinides (MAs) transmutation is a main design objective of advanced nuclear systems such as generation IV Sodium Fast Reactors (SFRs). In advanced fuel cycles, MA contents in final high level waste packages are main contributors to short term heat production as well as to long-term radiotoxicity. Therefore, MA transmutation would have an impact on repository designs and would reduce the environment burden of nuclear energy. In order to predict such consequences Monte Carlo (MC) transport codes are used in reactor design tasks and they are important complements and references for routinely used deterministic computational tools. In this paper two promising Monte Carlo transport-coupled depletion codes, EVOLCODE and SERPENT, are used to examine the impact of MA burning strategies in a SFR core, 3600MWth. The core concept proposal for MA loading in two configurations is the result of an optimization effort upon a preliminary reference design to reduce the reactivity insertion as a consequence of sodium voiding, one of the main concerns of this technology. The objective of this paper is double. Firstly, efficiencies of the two core configurations for MA transmutation are addressed and evaluated in terms of actinides mass changes and reactivity coefficients. Results are compared with those without MA loading. Secondly, a comparison of the two codes is provided. The discrepancies in the results are quantified and discussed. [Copyright &y& Elsevier]

Abstract: In this paper, we assess the impact of activation cross-section uncertainties on relevant fuel cycle parameters for a conceptual design of a modular European Facility for Industrial Transmutation (EFIT) with a “double strata” fuel cycle. Next, the nuclear data requirements are evaluated so that the parameters can meet the assigned design target accuracies. Different discharge burn-up levels are considered: a low burn-up, corresponding to the equilibrium cycle, and a high burn-up level, simulating the effects on the fuel of the multi-recycling scenario. In order to perform this study, we propose a methodology in two steps. Firstly, we compute the uncertainties on the system parameters by using a Monte Carlo simulation, as it is considered the most reliable approach to address this problem. Secondly, the analysis of the results is performed by a sensitivity technique, in order to identify the relevant reaction channels and prioritize the data improvement needs. Cross-section uncertainties are taken from the EAF-2007/UN library since it includes data for all the actinides potentially present in the irradiated fuel. Relevant uncertainties in some of the fuel cycle parameters have been obtained, and we conclude with recommendations for future nuclear data measurement programs, beyond the specific results obtained with the present nuclear data files and the limited available covariance information. A comparison with the uncertainty and accuracy analysis recently published by the WPEC-Subgroup26 of the OECD using BOLNA covariance matrices is performed. Despite the differences in the transmuter reactor used for the analysis, some conclusions obtained by Subgroup26 are qualitatively corroborated, and improvements for additional cross sections are suggested. [ABSTRACT FROM AUTHOR]

A series of neutron capture cross section measurements of interest to nuclear astrophysics have been recently performed at n_TOF, the neutron spallation source operating at CERN. The low repetition frequency of the proton beam driver, the extremely high instantaneous neutron flux, and the low background conditions in the experimental area are optimal for capture cross section measurements on low-mass or radioactive samples. An overview of the measurements performed during the two experimental campaigns in 2002 and 2003 is presented with special emphasis on the measurement of the capture cross sections of the Os isotopes relevant for the cosmochronology based on the Re/Os clock. [Copyright &y& Elsevier]

Within the frame of the EU H2020 program SANDA project, sensitivity and uncertainty analyses have been performed for the ESFR, ASTRID and ALFRED reactor concepts and the multi-purpose flexible irradiation facility MYRRHA. Relevant reactor parameters, namely the effective multiplication factor, the effective delayed neutron fraction, the Doppler reactivity coefficient, the void worth and the worth of control rods have been investigated. SCALE, Serpent 2 and MCNP6.2+SUMMON codes together with the covariance data of the JEFF-3.3 nuclear data library have been used for this study. A ranking of the most important isotopes and reactions impacting the mentioned parameters has been derived for all these systems. Uncertainties have been quantified and have been found to be higher than the target accuracies proposed. Therefore, recommendations for improvement of nuclear data are given. [ABSTRACT FROM AUTHOR]

• Differences in ANICCA and TR_EVOL nuclear fuel cycle simulators have been quantified. • The main source of uncertainty is the interpretation of the scenario specifications. • The different irradiations introduce a non-negligible cumulative effect. • Scenarios with multi-recycling and long-term studies are more affected by the code. Uncertainty propagation and quantification, when applied to the field of nuclear fuel cycle scenario studies, usually only considers a set of easily quantifiable input parameters, leaving out the effects of the modelling approaches. In order to extend the validity of these analyses, two different codes, ANICCA and TR_EVOL (developed respectively by SCK·CEN and CIEMAT), have been benchmarked through a study of an advanced and realistic nuclear fuel cycle scenario with the aim of assessing the impact of the use of different tools in the fuel cycle scenario uncertainty quantification. Additionally, a classical uncertainty propagation analysis was done following the total Monte Carlo and sensitivity approaches in order to compare the system uncertainties with the dissimilarities due the simulators. Results shows that the impact of the fuel cycle simulators cannot be neglected for certain observables, and that their effects become relevant as the scenarios extends over time due their cumulative effect. [ABSTRACT FROM AUTHOR]

Abstract Urban development, growing industrialization, and increasing demand for mobility have led to elevated levels of air pollution in many large cities in Latin America, where air quality standards and WHO guidelines are frequently exceeded. The conurbation of the metropolitan area of La Paz/El Alto is one of the fastest growing urban settlements in South America with the particularity of being located in a very complex terrain at a high altitude. As many large cities or metropolitan areas, the metropolitan area of La Paz/El Alto and the Altiplano region are facing air quality deterioration. Long-term measurement data of the equivalent black carbon (eBC) mass concentrations and particle number size distributions (PNSD) from the Global Atmosphere Watch Observatory Chacaltaya (CHC; 5240 m a.s.l., above sea level) indicated a systematic transport of particle matter from the metropolitan area of La Paz/El Alto to this high altitude station and subsequently to the lower free troposphere. To better understand the sources and the transport mechanisms, we conducted eBC and PNSDs measurements during an intensive campaign at two locations in the urban area of La Paz/El Alto from September to November 2012. While the airport of El Alto site (4040 m a.s.l.) can be seen as representative of the urban and Altiplano background, the road site located in Central La Paz (3590 m a.s.l.) is representative for heavy traffic-dominated conditions. Peaks of eBC mass concentrations up to 5 μg m−3 were observed at the El Alto background site in the early morning and evening, while minimum values were detected in the early afternoon, mainly due to thermal convection and change of the planetary boundary layer height. The traffic-related eBC mass concentrations at the road site reached maximum values of 10–20 μg m−3. A complete traffic ban on the specific Bolivian Day of Census (November 21, 2012) led to a decrease of eBC below 1 μg m−3 at the road site for the entire day. Compared to the day before and after, particle number concentrations decreased by a factor between 5 and 25 over the particle size range from 10 to 800 nm, while the submicrometer particle mass concentration dropped by approximately 80%. These results indicate that traffic is the dominating source of BC and particulate air pollution in the metropolitan area of La Paz/El Alto. In general, the diurnal cycle of eBC mass concentration at the Chacaltaya observatory is anti-correlated to the observations at the El Alto background site. This pattern indicates that the traffic-related particulate matter, including BC, is transported to higher altitudes with the developing of the boundary layer during daytime. The metropolitan area of La Paz/El Alto seems to be a significant source for BC of the regional lower free troposphere. From there, BC can be transported over long distances and exert impact on climate and composition of remote southern hemisphere. Highlights • The nation-wide traffic ban during the national Day of Census in Bolivia. • Traffic counts for 80% of the total particle mass concentration. • Diurnal cycle of BC at the Alti Plano with noon minimum due to thermal convection. • BC at Chacaltaya shows the opposite behavior with a maximum at noon. • Indication of transport of traffic-related BC into the lower free troposphere. [ABSTRACT FROM AUTHOR]

The advancement of the design of ALFRED beyond the conceptual phase, passes through the analysis of the impact of uncertainties, notably to what concerns safety-related conditions. Compliancy of plant safety to Design Extension Conditions is, according to IAEA and in line with the meaning itself of these beyond-design conditions, usually investigated by best estimates only. Due however to the demonstration nature of ALFRED, it was decided to assess the actual safety performances of this system even in ultimate conditions. To this regard, the emphasis was put on unprotected events like the UTOP (unprotected transient of over-power) and ULOOP (unprotected loss of offsite power, resulting from the combination of a loss of flow and loss of heat sink under unprotected conditions), pinpointed as the most challenging situations sought for the plant. The purpose of the present work, which has been divided in three parts, was then to assess the ultimate ALFRED safety margins against failure of the key core components and systems (Part III). To target this objective, the evaluation of uncertainties coming, on one hand, from nuclear data was performed at first, to retrieve their impact on the reactivity coefficients, thereby on the transient behavior driven by the latter (Part I); then, uncertainties from material properties, fabrication procedures, operation and computational tools were propagated to assess their influence on the thermal-hydraulics of the system (Part II). In this paper, presenting the first part of the work, the focus is on nuclear data. As such, a sensitivity/uncertainty analysis of the ALFRED core on key elementary reactivity effects, forming the basis for computing the feedback coefficients, has been performed. The sensitivity analysis allowed pointing out firstly the most relevant cross-sections for every response function. Uncertainty analysis allowed then establishing a possible range of confidence for the reactivity effects. The adjoint-based technique implemented in the TSUNAMI-3D module of the SCALE6 system was used. The confidence intervals identified for each reactivity effect have been combined then into confidence intervals for the feedback coefficients. Finally, the most conservative, yet physically sound (i.e., where correlations among coefficients, stemming from dependencies on common nuclear data, are taken into account), set of reactivity coefficients has been picked out from the confidence intervals, enabling transient calculations to propagate uncertainties into transient behavior. Using this off-nominal set, and comparing results with the reference ones, exploiting the system codes SIM-LFR and RELAP, a negligible effect of nuclear data uncertainties has been found for the ULOOP, while an increase of the maximum achieved power of around 6% has been computed for the UTOP. Overall, a modest contribution of nuclear data uncertainties for these transients has been found which, however, must be combined with the thermal-hydraulics one so to finally assess safety margins. [ABSTRACT FROM AUTHOR]

Mobility particle size spectrometers (MPSS) belong to the essential instruments in aerosol science that determine the particle number size distribution (PNSD) in the submicrometer size range. Following calibration procedures and target uncertainties against standards and reference instruments are suggested for a complete MPSS quality assurance program: (a) calibration of the CPC counting efficiency curve (within 5% for the plateau counting efficiency; within 1 nm for the 50% detection efficiency diameter), (b) sizing calibration of the MPSS, using a certified polystyrene latex (PSL) particle size standard at 203 nm (within 3%), (c) intercomparison of the PNSD of the MPSS (within 10% and 20% of the dN/dlogDP concentration for the particle size range 20–200 and 200–800 nm, respectively), and (d) intercomparison of the integral PNC of the MPSS (within 10%). Furthermore, following measurement uncertainties have been investigated: (a) PSL particle size standards in the range from 100 to 500 nm match within 1% after sizing calibration at 203 nm. (b) Bipolar diffusion chargers based on the radioactive nuclides Kr85, Am241, and Ni63and a new ionizer based on corona discharge follow the recommended bipolar charge distribution, while soft X-ray-based charges may alter faster than expected. (c) The use of a positive high voltage supply show a 10% better performance than a negative one. (d) The intercomparison of the integral PNC of an MPSS against the total number concentration is still within the target uncertainty at an ambient pressure of approximately 500 hPa. Copyright © 2018 Published with license by American Association for Aerosol Research [ABSTRACT FROM PUBLISHER]

Immune complexes (ICs) are the direct and real-time products of humoral immune responses. The identification of constituent foreign or autoantigens within ICs might bring new insights into the pathology of infectious diseases. We applied immune complexome analysis of plasma to the study of Chagas disease caused by Trypanosoma cruzi. Twenty seropositive plasma samples including cardiac and/or megacolon determinate patients (n = 11) and indeterminate (n = 9) were analysed along with 10 seronegative individuals to characterize the antigens bound to circulating ICs. We identified 39 T. cruzi antigens and 114 human autoantigens specific to patients with Chagas. Among those antigens, two T. cruzi antigens (surface protease GP63, glucose-6-isomerase) and six human autoantigens (CD180 antigen, ceruloplasmin, fibrinogen beta chain, fibrinogen beta chain isoform 2 preprotein, isoform gamma-A of fibrinogen cchain, serum paraoxonase) were detected in more than 50% of the patients tested. Human isoform short of complement factor H-related protein 2 and trans-sialidase of T. cruzi were more frequently found in the indeterminate (5/9 for both) compared with in the determinate Chagas (0/11, P = 0.046 for human, 1/11, P = 0.0498 for T. cruzi). The immune complexome could illustrate the difference of immune status between clinical forms of chronic Chagas disease. [ABSTRACT FROM AUTHOR]