5,824 research outputs found

    Application of genomic and quantitative genetic tools to identify candidate resistance genes for brown rot resistance in peach.

    Get PDF
    The availability of a complete peach genome assembly and three different peach genome sequences created by our group provide new opportunities for application of genomic data and can improve the power of the classical Quantitative Trait Loci (QTL) approaches to identify candidate genes for peach disease resistance. Brown rot caused by Monilinia spp., is the most important fungal disease of stone fruits worldwide. Improved levels of peach fruit rot resistance have been identified in some cultivars and advanced selections developed in the UC Davis and USDA breeding programs. Whole genome sequencing of the Pop-DF parents lead to discovery of high-quality SNP markers for QTL genome scanning in this experimental population. Pop-DF created by crossing a brown rot moderately resistant cultivar 'Dr. Davis' and a brown rot resistant introgression line, 'F8,1-42', derived from an initial almond × peach interspecific hybrid, was evaluated for brown rot resistance in fruit of harvest maturity over three seasons. Using the SNP linkage map of Pop-DF and phenotypic data collected with inoculated fruit, a genome scan for QTL identified several SNP markers associated with brown rot resistance. Two of these QTLs were placed on linkage group 1, covering a large (physical) region on chromosome 1. The genome scan for QTL and SNP effects predicted several candidate genes associated with disease resistance responses in other host-pathogen systems. Two potential candidate genes, ppa011763m and ppa026453m, may be the genes primarily responsible for M. fructicola recognition in peach, activating both PAMP-triggered immunity (PTI) and effector-triggered immunity (ETI) responses. Our results provide a foundation for further genetic dissection, marker assisted breeding for brown rot resistance, and development of peach cultivars resistant to brown rot

    Temporal Griffiths Phases

    Get PDF
    Disorder is an unavoidable ingredient of real systems. Spatial disorder generates Griffiths phases (GPs) which, in analogy to critical points, are characterized by a slow relaxation of the order parameter and divergences of quantities such as the susceptibility. However, these singularities appear in an extended region of the parameter space and not just at a (critical) point, i.e. there is generic scale invariance. Here, we study the effects of temporal disorder, focusing on systems with absorbing states. We show that for dimensions d2d \geq 2 there are Temporal Griffiths phases (TGPs) characterized by generic power-law spatial scaling and generic divergences of the susceptibility. TGPs turn out to be a counterpart of GPs, but with space and time playing reversed roles. TGPs constitute a unifying concept, shedding light on the non-trivial effects of temporal disorder.Comment: 4 pages, 3 figures; Accepted in PR

    A Bethe lattice representation for sandpiles

    Full text link
    Avalanches in sandpiles are represented throughout a process of percolation in a Bethe lattice with a feedback mechanism. The results indicate that the frequency spectrum and probability distribution of avalanches resemble more to experimental results than other models using cellular automata simulations. Apparent discrepancies between experiments are reconciled. Critical behavior is here expressed troughout the critical properties of percolation phenomena.Comment: 5 pages, 4 figures, submitted for publicatio

    Fenómenos de inundación subterránea asociados a las crecidas del río Ebro en la ciudad de Zaragoza

    Get PDF
    En este trabajo se estudia desde un punto de vista cuantitativo la respuesta hidráulica del acuífero aluvial urbano de Zaragoza a las crecidas del río Ebro con el objetivo del estudio de fenómenos de inundación subterránea. La simulación de dicha respuesta mediante un modelo numérico de flujo ha hecho posible evaluar la interacción del nivel freático con las estructuras subterráneas próximas al río Ebro. Los resultados obtenidos han sido validados con afecciones documentadas demostrando la utilidad del modelo.Además, de estos resultados se desprende que un total de 107 edificios son susceptibles de interaccionar con el agua subterránea donde las estructuras pueden llegar a ser sometidas a presiones hidrostáticas de hasta 0,7 kg·cm-2 dependiendo de la profundidad de la estructura y de la crecida considerada. The objective of this work is to study groundwater inundation phenomena in the metropolitan area of Zaragoza as a consequence of Ebro river flood events. A groundwater flow numerical model has been used to simulate the hydraulic response of the urban groundwater body to flood events in order to quantify the groundwater-building basements interaction. The model developed has been validated with damage documented proving its utility. The results showed that 107 buildings are vulnerable to groundwater inundation and that the structures affected may experience a pressure load up to 0.7 kg·cm-2 depending on the structure depth and the flood event considered

    Propagación de la recarga inducida por una crecida del río Ebro en el acuífero aluvial urbano de Zaragoza (España).

    Get PDF
    En este artículo se estudia desde un punto de vista cuantitativo la recarga del acuífero aluvial urbano de Zaragoza inducida por una crecida del río Ebro.Mediante la implementación de un modelo numérico de flujo se ha simulado la propagación de la crecida por el acuífero aluvial. Los resultados obtenidos muestran una dinámica de la recarga estrechamente ligada a la anisotropía de la transmisividad y las relaciones río-acuífero previas a la crecida. En general se produce un avance del frente de la recarga rápido, velocidades de 35-45 m·h-1 en las primeras 20 horas. Posteriormente, dicho frente experimenta una importante deceleración con velocidades muy bajas entorno al inicio de la curva de decrecida del río Ebro. El alcance de la recarga es de 1.000 m en zonas fuertemente efluentes previamente a la crecida y de 2.000-2.500 m en otras zonas. This paper studies the recharge induced by a flood event in the alluvial urban aquifer of Zaragoza from a quantitative point of view. Thanks to the implementation of a groundwater flow numerical model, the propagation of the recharge front through the alluvial aquifer has been simulated. The results obtained have shown a propagation of the recharge front through the aquifer driven by the transmissivity field and the existent river-aquifer regime prior to the flood event. In general, the recharge front has a 35-45 m·h-1 displacement in the first 20 hours. Subsequently, the front decelerates to almost zero velocity at the flood peak. Finally, it is concluded that the recharge front reaches 1,000 m in previous river effluent zones and 2,000- 2,500 m in other zones

    Versatile Graphene-Based Platform for Robust Nanobiohybrid Interfaces

    Get PDF
    Technologically useful and robust graphene-based interfaces for devices require the introduction of highly selective, stable, and covalently bonded functionalities on the graphene surface, whilst essentially retaining the electronic properties of the pristine layer. This work demonstrates that highly controlled, ultrahigh vacuum covalent chemical functionalization of graphene sheets with a thiol-terminated molecule provides a robust and tunable platform for the development of hybrid nanostructures in different environments. We employ this facile strategy to covalently couple two representative systems of broad interest: metal nanoparticles, via S-metal bonds, and thiol-modified DNA aptamers, via disulfide bridges. Both systems, which have been characterized by a multi-technique approach, remain firmly anchored to the graphene surface even after several washing cycles. Atomic force microscopy images demonstrate that the conjugated aptamer retains the functionality required to recognize a target protein. This methodology opens a new route to the integration of high-quality graphene layers into diverse technological platforms, including plasmonics, optoelectronics, or biosensing. With respect to the latter, the viability of a thiol-functionalized chemical vapor deposition graphene-based solution-gated field-effect transistor array was assessed

    Evolution of Phenolic Content, Antioxidant Capacity and Phenolic Profile during Cold Pre-fermentative Maceration and Subsequent Fermentation of Cabernet Sauvignon Red Wine

    Get PDF
    The phenolic compound profile and content of red wines are modified during the maceration-fermentation process by several factors that alter the extractability of the compounds and by reactions that phenolic compounds undergo, and can be directly related to the quality of the final wine and its beneficial effects on the consumer. The aim of this study was to determine the change in phenolic content and profile during cold pre-fermentative maceration and fermentation without the removal of grape pomace. Total phenolics,flavonoids, anthocyanins, tannins and antioxidant capacity were determined by spectrophotometric methods, and the phenolic profile was determined by HPLC-MS on each day of the maceration-fermentation process. The results showed a variation in the content of phenolic compounds and antioxidant activity over time, but the final phenolic content showed no significative difference compared with the initial content (1 268 mg GAE/L and 1 115 mg GAE/L respectively). The phenolic profile showed that flavonoids were theprincipal compounds in wine and that they increased at the end of the winemaking. Condensed tannins also increased during fermentation, while anthocyanins and some phenolic acids decreased at the end of the process. The final content of phenolic compounds was similar to the initial one, but there was a change in the different fractions of phenolic compounds at the end of fermentation

    La modelización tridimensional del flujo del agua subterránea y transporte de calor en la gestión de recursos geotérmicos someros en zonas urbanas

    Get PDF
    La planificación del uso geotérmico del agua subterránea en acuíferos someros urbanos requiere un modelo numérico capaz de reproducir los efectos de la explotación actual y ser capaz de predecir los impactos derivados de dicha actividad. En este trabajo se presenta el desarrollo preliminar de un modelo numérico que puede contribuir a mejorar la gestión de los recursos geotérmicos someros en la ciudad de Zaragoza. El modelo numérico permite implementar toda la información hidrogeológica y térmica recopilada, explicar esta información de forma coherente reproduciendo la física de fluidos y termodinámica en medios poroso s y predecir a medio y largo plazo los impactos producidos. Finalmente se muestran las posibilidades y ventajas derivadas del uso del modelo numérico en la gestión de permisos de concesión de derechos de explotación para nuevos aprovechamientos. The management of the thermal use of groundwater in shallow urban aquifers requires a numerical model capable of reproducing the impacts of actual exploitations and of predicting further impacts in the future. In this work, the numerical model developed for the management of shallow geothermal resources in the city of Zaragoza (Spain) is presented. The model allows to explain the data coherent with the fluid physics and the heat transport in porous media and also provide predictions for the thermal impacts at mid- and long-term. Finally, the possibilities and advantages derived from the use of the numerical modelling for the concession process of new exploitation licenses are described

    The Energy of a Moving Quark-Antiquark Pair in an N=4 SYM Plasma

    Full text link
    We make use of the AdS/CFT correspondence to determine the energy of an external quark-antiquark pair that moves through strongly-coupled thermal N=4 super-Yang-Mills plasma, both in the rest frame of the plasma and in the rest frame of the pair. It is found that the pair feels no drag force, has an energy that reproduces the expected 1/L (or gamma/L) behavior at small quark-antiquark separations, and becomes unbound beyond a certain screening length whose velocity-dependence we determine. We discuss the relation between the high-velocity limit of our results and the lightlike Wilson loop proposed recently as a definition of the jet-quenching parameter.Comment: LaTeX 2e, 27 pages, 8 eps figures; v2: added computation of the pair energy in the plasma rest frame, clarified the comparison with hep-ph/0607062, corrected typos, added reference

    The GB4.0 Platform, an All-In-One Tool for CRISPR/Cas-Based Multiplex Genome Engineering in Plants

    Get PDF
    CRISPR/Cas ability to target several loci simultaneously (multiplexing) is a game-changer in plant breeding. Multiplexing not only accelerates trait pyramiding but also can unveil traits hidden by functional redundancy. Furthermore, multiplexing enhances dCas-based programmable gene expression and enables cascade-like gene regulation. However, the design and assembly of multiplex constructs comprising tandemly arrayed guide RNAs (gRNAs) requires scarless cloning and is still troublesome due to the presence of repetitive sequences, thus hampering a more widespread use. Here we present a comprehensive extension of the software-assisted cloning platform GoldenBraid (GB), in which, on top of its multigene cloning software, we integrate new tools for the Type IIS-based easy and rapid assembly of up to six tandemly-arrayed gRNAs with both Cas9 and Cas12a, using the gRNA-tRNA-spaced and the crRNA unspaced approaches, respectively. As stress tests for the new tools, we assembled and used for Agrobacterium-mediated stable transformation a 17 Cas9-gRNAs construct targeting a subset of the Squamosa-Promoter Binding Protein-Like (SPL) gene family in Nicotiana tabacum. The 14 selected genes are targets of miR156, thus potentially playing an important role in juvenile-to-adult and vegetative-to-reproductive phase transitions. With the 17 gRNAs construct we generated a collection of Cas9-free SPL edited T plants harboring up to 9 biallelic mutations and showing leaf juvenility and more branching. The functionality of GB-assembled dCas9 and dCas12a-based CRISPR/Cas activators and repressors using single and multiplexing gRNAs was validated using a Luciferase reporter with the Solanum lycopersicum Mtb promoter or the Agrobacterium tumefaciens nopaline synthase promoter in transient expression in Nicotiana benthamiana. With the incorporation of the new web-based tools and the accompanying collection of DNA parts, the GB4.0 genome edition turns an all-in-one open platform for plant genome engineering
    corecore