758 research outputs found
Evaluación de la peligrosidad sísmica en España para aplicaciones relacionadas con la seguridad nuclear. Resultados preliminares.
En este trabajo se presentan los avances realizados en el marco del proyecto “Evaluación de la Peligrosidad Sísmica en España para aplicaciones relacionadas con la seguridad nuclear” financiado por el Consejo de Seguridad Nuclear. La finalidad última del proyecto es ahondar en el conocimiento de la peligrosidad sísmica y de su incertidumbre en los emplazamientos de instalaciones críticas como instalaciones nucleares y almacenamientos de residuos radiactivos en nuestro país. Con ese propósito, una primera fase del proyecto está destinada a recopilar y estructurar toda la información generada en proyectos previos financiados por el CSN (DAÑOS, SIGMA, PRIOR, EXPEL y DATACIÓN) concerniente a estudio de fallas activas, análisis de paleosismicidad, catálogos sísmicos y de movimiento fuerte del suelo, etc.. Esta información está siendo integrada y unificada en una Base de Datos y en un Sistema de Información Geográfica. Paralelamente, el código informático desarrollado en el proyecto EXPEL está siendo actualizado para desarrollar cálculos de peligrosidad sísmica siguiendo la metodología PSHA de una forma eficiente, incluyendo formulación de un árbol lógico, cuantificación de incertidumbres epistémicas y aleatorias, análisis de sensibilidad de diferentes opciones en los resultados y desagregación. Los resultados preliminares del proyecto son presentados en esta comunicación, dando una orientación hacia futuros desarrollos y toma de decisiones relacionados con la seguridad nuclear
Circular strings, wormholes and minimum size
The quantization of circular strings in an anti-de Sitter background
spacetime is performed, obtaining a discrete spectrum for the string mass. A
comparison with a four-dimensional homogeneous and isotropic spacetime coupled
to a conformal scalar field shows that the string radius and the scale factor
have the same classical solutions and that the quantum theories of these two
models are formally equivalent. However, the physically relevant observables of
these two systems have different spectra, although they are related to each
other by a specific one-to-one transformation. We finally obtain a discrete
spectrum for the spacetime size of both systems, which presents a nonvanishing
lower bound.Comment: 11 pages, LaTeX2e, minor change
Isospin diffusion from 40,48Ca + 40,48Ca experimental data at Fermi energies: Direct comparisons with transport model calculations
This article presents an investigation of isospin equilibration in cross-bombarding 40,48 Ca + 40,48 Ca reactions at 35 MeV/nucleon, by comparing experimental data with filtered transport model calculations. Isospin diffusion is studied using the evolution of the isospin transport ratio with centrality. The asymmetry parameter δ = (N − Z )/A of the quasiprojectile (QP) residue is used as isospin-sensitive observable, while a recent method for impact parameter reconstruction is used for centrality sorting. A benchmark of global observables is proposed to assess the relevance of the antisymmetrized molecular dynamics (AMD) model, coupled to GEMINI++, in the study of dissipative collisions. Our results demonstrate the importance of considering cluster formation to reproduce observables used for isospin transport and centrality studies. Within the AMD model, we prove the applicability of the impact parameter reconstruction method, enabling a direct comparison to the experimental data for the investigation of isospin diffusion. For both, we evidence a tendency to isospin equilibration with an impact parameter decreasing from 9 to 3 fm, while the full equilibration is not reached. A weak sensitivity to the stiffness of the equation of state employed in the model is also observed, with a better reproduction of the experimental trend for the neutron-rich reactions.Departamento de Física Aplicad
Genomic and proteomic analyses reveal a relationship between WNT pathway, genes, oxidative stress metabolism and vascular calcification
Comunicaciones a congreso
Androgen receptor gene polymorphism influence fat accumulation: a longitudinal study from adolescence to adult age.
To determine the influence of androgen receptor CAG and GGN repeat polymorphisms on fat mass and maximal fat oxidation (MFO), CAG and GGN repeat lengths were measured in 128 young boys, from which longitudinal data were obtained in 45 of them [mean?±?SD: 12.8?±?3.6 years old at recruitment, and 27.0?±?4.8 years old at adult age]. Subjects were grouped as CAG short (CAGS ) if harboring repeat lengths ?21, the rest as CAG long (CAGL ); and GGN short (GGNS ) if GGN repeat lengths ?23, or long if >?23 (GGNL ). CAGS and GGNS were associated with lower adiposity than CAGL or GGNL (P?<?0.05). There was an association between the logarithm of CAG repeats polymorphism and the changes of body mass (r?=?0.34, P?=?0.03). At adult age, CAGS men showed lower accumulation of total body and trunk fat mass, and lower resting metabolic rate (RMR) and MFO per kg of total lean mass compared with CAGL (P?<?0.05). GGNS men also showed lower percentage of body fat (P?<?0.05). In summary, androgen receptor CAG and GGN repeat polymorphisms are associated with RMR, MFO, fat mass, and its regional distribution in healthy male adolescents, influencing fat accumulation from adolescence to adult age
Enhancing dna immunization by targeting asfv antigens to sla-ii bearing cells
One of the main criticisms to DNA vaccines is the poor immunogenicity that they confer on occasions, at least in large animals. Confirming this theory, immunization with plasmid DNA encoding two African swine fever virus genes in frame (pCMV-PQ), failed in inducing detectable immune responses in pigs, while it was successful in mice. Aiming to improve the immune responses induced in swine, a new plasmid was constructed, encoding the viral genes fused in frame with a single chain variable fragment of an antibody specific for a swine leukocyte antigen II (pCMV-APCH1PQ). Our results clearly demonstrate that targeting antigens to antigen professional cells exponentially enhanced the immune response induced in pigs, albeit that the DNA vaccine was not able to confer protection against lethal viral challenge. Indeed, a viremia exacerbation was observed in each of the pigs that received the pCMV-APCH1PQ plasmid, this correlating with the presence of non-neutralizing antibodies and antigen-specific SLA II-restricted T-cells. The implications of our discoveries for the development of future vaccines against African swine fever virus and other swine pathogens are discussed.Fil: Argilaguet, J. M.. No especifíca;Fil: Pérez Martín, E.. No especifíca;Fil: Gallardo, C.. No especifíca;Fil: Salguero, F. J.. No especifíca;Fil: Borrego, B.. No especifíca;Fil: Lacasta, A.. No especifíca;Fil: Accensi, F.. No especifíca;Fil: Díaz, I.. No especifíca;Fil: Nofrarías, M.. No especifíca;Fil: Pujols, J.. No especifíca;Fil: Blanco, E.. No especifíca;Fil: Pérez Filgueira, Daniel Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Escribano, José M.. No especifíca;Fil: Rodríguez, F.. No especifíca
Hepatic insulin resistance both in prediabetic and diabetic patients determines postprandial lipoprotein metabolism: from the CORDIOPREV study
Background/aims: Previous evidences have shown the presence of a prolonged and exaggerated postprandial
response in type 2 diabetes mellitus (T2DM) and its relation with an increase of cardiovascular risk. However, the
response in prediabetes population has not been established. The objective was to analyze the degree of postprandial
lipemia response in the CORDIOPREV clinical trial (NCT00924937) according to the diabetic status.
Methods: 1002 patients were submitted to an oral fat load test meal (OFTT) with 0.7 g fat/kg body weight [12 %
saturated fatty acids (SFA), 10 % polyunsaturated fatty acids (PUFA), 43 % monounsaturated fatty acids (MUFA), 10 %
protein and 25 % carbohydrates]. Serial blood test analyzing lipid fractions were drawn at 0, 1, 2, 3 and 4 h during
postprandial state. Postprandial triglycerides (TG) concentration at any point >2.5 mmol/L (220 mg/dL) has been
established as undesirable response. We explored the dynamic response in 57 non-diabetic, 364 prediabetic and 581
type 2 diabetic patients. Additionally, the postprandial response was evaluated according to basal insulin resistance
subgroups in patients non-diabetic and diabetic without pharmacological treatment (N = 642).
Results: Prevalence of undesirable postprandial TG was 35 % in non-diabetic, 48 % in prediabetic and 59 % in diabetic
subgroup, respectively (p < 0.001). Interestingly, prediabetic patients displayed higher plasma TG and large triacylglycerol-
rich lipoproteins (TRLs-TG) postprandial response compared with those non-diabetic patients (p < 0.001
and p = 0.003 respectively). Moreover, the area under the curve (AUC) of TG and AUC of TRLs-TG was greater in the
prediabetic group compared with non-diabetic patients (p < 0.001 and p < 0.005 respectively). Patients with liver
insulin resistance (liver-IR) showed higher postprandial response of TG compared with those patients with muscle-IR
or without any insulin-resistance respectively (p < 0.001).
Conclusions: Our findings demonstrate that prediabetic patients show a lower phenotypic flexibility after external
aggression, such as OFTT compared with nondiabetic patients. The postprandial response increases progressively
according to non-diabetic, prediabetic and type 2 diabetic state and it is higher in patients with liver insulin-resistance.
To identify this subgroup of patients is important to treat more intensively in order to avoid future cardiometabolic
complications
Damping mechanisms for oscillations in solar prominences
Small amplitude oscillations are a commonly observed feature in
prominences/filaments. These oscillations appear to be of local nature, are
associated to the fine structure of prominence plasmas, and simultaneous flows
and counterflows are also present. The existing observational evidence reveals
that small amplitude oscillations, after excited, are damped in short spatial
and temporal scales by some as yet not well determined physical mechanism(s).
Commonly, these oscillations have been interpreted in terms of linear
magnetohydrodynamic (MHD) waves, and this paper reviews the theoretical damping
mechanisms that have been recently put forward in order to explain the observed
attenuation scales. These mechanisms include thermal effects, through
non-adiabatic processes, mass flows, resonant damping in non-uniform media, and
partial ionization effects. The relevance of each mechanism is assessed by
comparing the spatial and time scales produced by each of them with those
obtained from observations. Also, the application of the latest theoretical
results to perform prominence seismology is discussed, aiming to determine
physical parameters in prominence plasmas that are difficult to measure by
direct means.Comment: 36 pages, 16 figures, Space Science Reviews (accepted
Italian Ryegrass Establishment by Self-Seeding in Integrated Crop-Livestock Systems: Effects of Grazing Management
Recent reports have indicated that integrated crop-livestock systems (ICLS) can enhance sustained crop and livestock production by efficiently using agricultural system resources (Liu et al. 2012). In the subtropical South American regions, soybean (Glycine max L. Merril) and maize (Zea Mays L.) crops are widely grown after Italian ryegrass (Lolium multiflorum Lam) pastures. In this system, the pasture may be established by self-seeding. Self-seedling reduces pasture production costs and extends the grazing period. The stoking method, and especially the grazing intensity, can greatly affect the quantity of seeds added to the soil by affecting the demography of the reproductive tillers. In subtropical areas where Italian ryegrass is used for winter pastures in ICLSs, the effects of crop rotation, stocking methods or grazing intensities on the subsequent ability of Italian ryegrass to self-seed are unknown.
The objectives of this study are to evaluate the effects of management practices (crop rotation, stocking method and herbage allowance) on the establishment of Italian ryegrass pastures by self-seedling in an ICLS
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