Propagation of Statistical and Nuclear Data Uncertainties in Monte-Carlo Burn-up Calculations

Two methodologies to propagate the uncertainties on the nuclide inventory in combined Monte Carlo-spectrum and burn-up calculations are presented, based on sensitivity/uncertainty and random sampling techniques (uncertainty Monte Carlo method). Both enable the assessment of the impact of uncertainties in the nuclear data as well as uncertainties due to the statistical nature of the Monte Carlo neutron transport calculation. The methodologies are implemented in our MCNP–ACAB system, which combines the neutron transport code MCNP-4C and the inventory code ACAB. A high burn-up benchmark problem is used to test the MCNP–ACAB performance in inventory predictions, with no uncertainties. A good agreement is found with the results of other participants. This benchmark problem is also used to assess the impact of nuclear data uncertainties and statistical flux errors in high burn-up applications. A detailed calculation is performed to evaluate the effect of cross-section uncertainties in the inventory prediction, taking into account the temporal evolution of the neutron flux level and spectrum. Very large uncertainties are found at the unusually high burn-up of this exercise (800 MWd/kgHM). To compare the impact of the statistical errors in the calculated flux with respect to the cross uncertainties, a simplified problem is considered, taking a constant neutron flux level and spectrum. It is shown that, provided that the flux statistical deviations in the Monte Carlo transport calculation do not exceed a given value, the effect of the flux errors in the calculated isotopic inventory are negligible (even at very high burn-up) compared to the effect of the large cross-section uncertainties available at present in the data files

Contribuciones a la flora del Sistema Ibérico, 9

Se dan notícias corológicas sobre 22 táxones vasculares raras o poco conocidas en la zona, localizadas en el Sistema Ibérico a su paso por las provincias de Cuenca, Guadalajara, Teruel y [email protected]

A new hybrid taxon on genus Thymus L. collected in Aragón (Spain)

MXrEo SANZ, G.; MERcADAL FERRERUELA, N. E. & Písco GARCÍA, J. M. 1995. Sobre un hibrido nuevo del género Thymus L. detectado en Aragón. Bot. Complutensis 20: 69-73. Se comunica el hallazgo de un nuevo hibrido del género Thwnus L. (Labiatae) en la provincia de Teruel, el cual se describe con el nombre de Th. x henitoi Mateo, Mercadal & Pisco, nothosp. nswa, alquc se le supone la combinación parental Th. godayanus Rivas-Martínez et al. x Ni. pulegioides L.Málvo SANZ. G.; MERCADAI. FERRERtJELA, N. E. & Písco GARCÍA, J. M, 1995. A new hybrid taxon on genus Thymus L. collected in Aragón (Spain). BoL Coniplutensis 20: 69-73. A new nothospccics belonging to the genus Thvmus L. (Labiatae) coming from Teruel province (Aragon, NE Spain) is described. The new name proposed is Th. benitoi Mateo, Mercadal & Pisco, nothosp. nova. which its presumed parents are Ni. goda yanas Rivas-Martínez eraL and ib. pulegioides L

Impact of different correlation structures in cross-section covariance matrices on the inventory and inventory-related parameters

At present, cross section correlation data are very poorly known. This work can be helpful to evaluate the effort that the international community should devote to the improvement of correlation data for inventory prediction in nuclear systems. Our purpose is to assess the impact of different correlation structures on the uncertainties in relevant fuel cycle and repository parameters, using fixed variances/diagonal values in the cross section covariance matrices. At this stage, only correlation in energy is taken into account, and no correlation among different types of nuclear reactions or different isotopes is considered. To accomplish this goal, the inventory code ACAB is used to estimate the uncertainties in the actinide concentrations of the irradiated fuel, related decay heat and dose (radiotoxicity) in a representative ADS irradiation scenario. It is shown that the nature of the introduced correlations is very relevant to estimate the overall uncertainty in those parameters, and then, the need of more scientifically based correlation data is clearly justified

An unprecedented use for glycerol: chemoselective reducing agent for sulfoxides

A new application for glycerol that expands its possibilities beyond a green solvent and a precursor of value-added products has been demonstrated. Simple, easily available, and environmentally friendly dioxomolybdenum( VI) complexes are highly efficient catalysts for the chemoselective sulfoxide deoxygenation with this biomass-derived chemical feedstock. Both refined glycerol and crude glycerin can be used, thus expanding the potential application of this reaction. Subsequent transformation of glycerol during this reductive process has also been investigatedMinisterio de Ciencia e Innovacion (MICINN), FEDER (CTQ2010-15358 and CTQ2009-09949/BQU), Junta de Castilla y Leon (BU021A09 and GR-172), MICINN ("Juan de la Cierva" and "Ramon y Cajal" contracts for P.G.-G. and M.A.F.-R.

Impact of different correlation structures in cross-section covariance matrices on the inventory and inventory-related parameters

Abstract At present, cross section correlation data are very poorly known. This work can be helpful to evaluate the effort that the international community should devote to the improvement of correlation data for inventory prediction in nuclear systems. Our purpose is to assess the impact of different correlation structures on the uncertainties in relevant fuel cycle and repository parameters, using fixed variances/diagonal values in the cross section covariance matrices. At this stage, only correlation in energy is taken into account, and no correlation among different types of nuclear reactions or different isotopes is considered. To accomplish this goal, the inventory code ACAB is used to estimate the uncertainties in the actinide concentrations of the irradiated fuel, related decay heat and dose (radiotoxicity) in a representative ADS irradiation scenario. It is shown that the nature of the introduced correlations is very relevant to estimate the overall uncertainty in those parameters, and then, the need of more scientifically based correlation data is clearly justified

Effects of water pollution and river fragmentation on population genetic structure of invasive mosquitofish

We analyzed variation at the GPI-2 locus and eleven microsatellite loci of eastern mosquitofish Gambusia holbrooki populations introduced to the Ebro River (Spain), sampling above and below a dam (Flix Reservoir) where severe chronic pollution has been well documented. Allele frequency changes at the GPI-2 locus in the sites nearest to the polluted sediments agree with previous results from studies in mercury-exposed populations of this highly invasive fish. Genetic distinction of the mosquitofish collected close to the polluted sediments was detected at the GPI locus but also at the presumptive neutral microsatellite loci. Recent migration rates estimated from microsatellites indicated that around 30% of fish collected in a specific location were immigrants from upstream and downstream sources. Such high migration rates probably contribute to the mosquitofish's invasive success and suggest that the consequences on the mosquitofish regional genetic structured of high levels of water toxicants could be mediated by immigration from other sites, but the effect of pollutants on local diversity might be higher than observed here.info:eu-repo/semantics/acceptedVersio

Marine GIS Applications: GIS Spanish Institute of Oceanography

Poster presentado en el SIEBM XVIII Simposio Ibérico de Biología MarinaSince 1998 in the IEO is developing a MARINE GIS with the objective of organize, harmonize, standardize, integrated the geo-information of IEO. GIS tools are used in several projects carried out in the IEO related to study of living resources, natural resources, studies of evolution of natural phenomena, collecting data, marine spatial planning, etc

Ecological successions throughout the desiccation of Tirez lagoon (Spain) as an astrobiological time-analog for wet-to-dry transitions on Mars

Tirez was a small and seasonal endorheic athalassohaline lagoon that was located in central Spain. In recent years, the lagoon has totally dried out, offering for the first time the opportunity to analyze its desiccation process as a “time-analog” to similar events occurred in paleolakes with varying salinity during the wet-to-dry transition on early Mars. On the martian cratered highlands, an early period of water ponding within enclosed basins evolved to a complete desiccation of the lakes, leading to deposition of evaporitic sequences during the Noachian and into the Late Hesperian. As Tirez also underwent a process of desiccation, here we describe (i) the microbial ecology of Tirez when the lagoon was still active 20 years ago, with prokaryotes adapted to extreme saline conditions; (ii) the composition of the microbial community in the dried lake sediments today, in many case groups that thrive in sediments of extreme environments; and (iii) the molecular and isotopic analysis of the lipid biomarkers that can be recovered from the sediments today. We discuss the implications of these results to better understanding the ecology of possible Martian microbial communities during the wet-to-dry transition at the end of the Hesperian, and how they may inform about research strategies to search for possible biomarkers in Mars after all the water was los

Heath-related quality of life in Spanish breast cancer patients: a systematic review

<p>Abstract</p> <p>Background</p> <p>Breast cancer is one of the oncological diseases in which health-related quality of life (HRQL) has been most studied. This is mainly due to its high incidence and survival. This paper seeks to: review published research into HRQL among women with breast cancer in Spain; analyse the characteristics of these studies; and describe the instruments used and main results reported.</p> <p>Methods</p> <p>The databases consulted were MEDLINE, EMBASE, PsycINFO, Dialnet, IBECS, CUIDEN, ISOC and LILACS. The inclusion criteria required studies to: 1) include Spanish patients, and a breakdown of results where other types of tumours and/or women from other countries were also included; and, 2) furnish original data and measure HRQL using a purpose-designed questionnaire. The methodological quality of studies was assessed.</p> <p>Results</p> <p>Spain ranked midway in the European Union in terms of the number of studies conducted on the HRQL of breast cancer patients. Of the total of 133 papers published from 1993 to 2009, 25 met the inclusion criteria. Among them, only 12 were considered as having good or excellent quality. A total of 2236 women participated in the studies analysed. In descending order of frequency, the questionnaires used were the EORTC, FACT-B, QL-CA-Afex, SF-12, FLIC, RSCL and CCV. Five papers focused on validation or adaptation of questionnaires. Most papers examined HRQL in terms of type of treatment. Few differences were detected by type of chemotherapy, with the single exception of worse results among younger women treated with radiotherapy. In the short term, better results were reported for all HRQL components by women undergoing conservative rather than radical surgery. Presence of lymphedema was associated with worse HRQL. Three studies assessed differences in HRQL by patients' psychological traits. Psychosocial disorder and level of depression and anxiety, regardless of treatment or disease stage, worsened HRQL. In addition, there was a positive effect among patients who reported having a "fighting spirit" and using "denial" as a defence mechanism. One study found that breast cancer patients scored worse than did healthy women on almost all SF-12 scales.</p> <p>Conclusion</p> <p>Research into health-related quality of life of breast-cancer patients is a little developed field in Spain.</p