34 research outputs found

    Cretaceous mycelia preserving fungal polysaccharides: taphonomic and paleoecological potential of microorganisms preserved in fossil resins

    Get PDF
    The cortices of pieces of Cretaceous amber around the world commonly are constituted by networks of filamentous structures. Based on their morphological characteristics, such structures have previously been classified in different microorganismal groups. Their correct interpretation, however, is of great importance to establish the conditions of the resin's burial in the forest litter, and can provide important clues regarding the ecology and environmental conditions of Cretaceous resinous forests. Because these networks of filamentous structures present typical fungal morphological features we conducted a study in order to resolve their origin. The cortices of several pieces of Cretaceous amber from Spain were examined using light and scanning electron microscopy, energy dispersive X-ray spectroscopy, and confocal laser scanning microscopy. This is the first time that Calcofluor white and Wheat germ agglutinin conjugated with fluorescein isothiocyanate have been employed as fungal markers in amber, and their use enabled us to detect preserved polysaccharides in the filamentous structures using confocal laser scanning microscopy. These results provide the first and oldest record of ß-1,3 and ß-1,4-linked polysaccharides, and specifically N-acetylglucosamine residues from chitin in a fossil fungus preserved in amber, and to demonstrate that the networks of filamentous structures are mycelia composed of profuse hyphae of a resinicolous fungus. This type of mycelium constitutes one of the largest fungal fossil records known. Using taphonomic data, it is demonstrated that the cortices originated during the Cretaceous due to fungal growth within non-solidified resin. The fossil diagenetic degradation sequence of the fungal hyphae and the surrounding amber is described. This degradation changed the microscopic appearance of the hyphae; thus, some of the previously indicated taxonomic features of this microorganism may actually be fossil diagenetic artifacts. The paleoecological implications with regard to fungal trophic requirements and forest environmental conditions are discusse

    Nanometric constrictions in superconducting coplanar waveguide resonators

    Get PDF
    We report on the design, fabrication and characterization of superconducting coplanar waveguide resonators with nanoscopic constrictions. By reducing the size of the center line down to 50 nm, the radio frequency currents are concentrated and the magnetic field in its vicinity is increased. The device characteristics are only slightly modified by the constrictions, with changes in resonance frequency lower than 1% and internal quality factors of the same order of magnitude as the original ones. These devices could enable the achievement of higher couplings to small magnetic samples or even to single molecular spins and have applications in circuit quantum electrodynamics, quantum computing and electron paramagnetic resonance.Comment: 4 pages, 4 figure

    Multi-dimensional barrier identification for wind farm repowering in Spain through an expert judgment approach

    Get PDF
    .Spain was one of the pioneers in the deployment of wind energy systems worldwide and thus since 2014 has a potential for repowering that reaches between 3.3 and 8.7 GW in 2021 (12%–32% of its current installed wind capacity). However, despite the technical and economic advantages, we have observed little interest from promoters in the repowering of already amortized wind farms. The aim of the proposed study is to depict the background framework of barriers for repowering wind farms, which is specially affecting to Spain, but that can also extend to other EU countries. Therefore, we conducted a systematic survey study with academics, promoters, financial experts, manufacturers, operators, maintainers and policymakers to identify and understand the existing real and practical barriers. As a result, we have identified 34 major barriers covering five categories: technical issues, economics, environmental considerations, social concerns, and regulatory and administrative hurdles. We then asked the experts to rate these barriers based on their impact or relevance. We found that the experts agree that regulatory and administrative barriers have the maximum impact, while economic, environmental and technical barriers have only a mid-high impact. Therefore, we can conclude that, in general, the Administration must develop a concise and stable regulatory framework for all RES, especially for repowering projects, and carry out a review of both the technical requirements and the incentives schemes, with a focus on energy efficiency.S

    Situación del reformismo

    Get PDF
    Fil: Bacigalupo, Enrique. Universidad de Buenos Aires. Facultad de Derecho. Buenos Aires, ArgentinaFil: Sanguinetti, Horacio. Universidad de Buenos Aires. Facultad de Derecho. Buenos Aires, ArgentinaFil: Ciria, Alberto. Universidad de Buenos Aires. Facultad de Derecho. Buenos Aires, Argentin

    Nanoscale constrictions in superconducting coplanar waveguide resonators

    Get PDF
    We report on the design, fabrication, and characterization of superconducting coplanar waveguide resonators with nanoscopic constrictions. By reducing the size of the center line down to 50 nm, the radio frequency currents are concentrated and the magnetic field in its vicinity is increased. The device characteristics are only slightly modified by the constrictions, with changes in resonance frequency lower than 1% and internal quality factors of the same order of magnitude as the original ones. These devices could enable the achievement of higher couplings to small magnetic samples or even to single molecular spins and have applications in circuit quantum electrodynamics, quantum computing, and electron paramagnetic resonance

    Plasma levels of mitochondrial and nuclear DNA in patients with massive pulmonary embolism in the emergency department: A prospective cohort study

    Get PDF
    Introduction: Cell-free plasma mitochondrial DNA (mt-DNA) and nuclear DNA (n-DNA) are biomarkers with prognostic utility in conditions associated with a high rate of cell death. This exploratory study aimed to determine the plasma levels of both nucleic acids in patients with massive and submassive pulmonary embolism (PE) and to compare them with other biomarkers, such as heart-type fatty acid-binding protein (H-FABP) and troponin I (Tn-I) Methods: This was a prospective observational study of 37 consecutive patients with massive PE, 37 patients with submassive PE, and 37 healthy subjects. Quantifications of plasma mt-DNA and n-DNA with real-time quantitative polymerase chain reaction (PCR), and plasma H-FABP and Tn-I by commercial assays, were done on blood samples drawn within 4 hours after presentation at the emergency department. Results: Plasma mt-DNA and n-DNA concentrations were much higher in patients with massive PE (median, 2,970 GE/ml; interquartile range (IQR), 1,050 to 5,485; and 3,325 GE/ml, IQR: 1,080 to 5,790, respectively) than in patients with submassive PE (870 GE/ml and 1,245 GE/ml, respectively; P < 0.01) or controls (185 GE/ml and 520 GE/ml, respectively). Eighteen patients with massive PE died of a PE-related cause by day 15 of observation. Plasma mt- DNA and n-DNA values were 2.3-fold and 1.9-fold higher in the subgroup of nonsurviving patients than in survivors. H-FABP and Tn-I values were also higher in patients with massive PE who died (7.3 ng/ml and 0.023 ng/ml, respectively) than in those who survived (6.4 ng/ml, and 0.016 ng/ml, respectively). By receiver operating curve (ROC) analysis, the best cutoff values for predicting 15-day mortality were 3,380 GE/ml for mt-DNA, 6.8 ng/ml for H-FABP, 3,625 GE/ml for n-DNA, and 0.020 ng/ml for Tn-I, based on the calculated areas under the curve (AUCs) of 0.89 (95% confidence interval (CI), 0.78 to 0.99), 0.76 (95% CI, 0.69 to 093), 0.73 (95% CI, 0.58 to 0.91), and 0.59 (95% CI, 0.41 to 0.79), respectively. By stepwise logistic regression, a plasma mt-DNA concentration greater than 3,380 GE/ml (adjusted odds ratio (OR), 8.22; 95% CI, 1.72 to 39.18; P 6.8 ng/ml (OR, 5.36; 95% CI, 1.06 to 27.08; P < 0.01) were the only independent predictors of mortality. Conclusions: mt-DNA and H-FBAP might be promising markers for predicting 15-day mortality in massive PE, with mt-DNA having better prognostic accuracy.This work was supported partially by grants from Plan Nacional I+D+I (SAF 2008-05347 and SAF2011-23575) and from Fundación Mutua Madrileña de Investigación Biomédica (2008 and 2011) to Francisco Arnalich and Carmen Montie

    Pasados y presente. Estudios para el profesor Ricardo García Cárcel

    Get PDF
    Ricardo García Cárcel (Requena, 1948) estudió Historia en Valencia bajo el magisterio de Joan Reglà, con quien formó parte del primer profesorado de historia moderna en la Universidad Autónoma de Barcelona. En esta universidad, desde hace prácticamente cincuenta años, ha desarrollado una extraordinaria labor docente y de investigación marcada por un sagaz instinto histórico, que le ha convertido en pionero de casi todo lo que ha estudiado: las Germanías, la historia de la Cataluña moderna, la Inquisición, las culturas del Siglo de Oro, la Leyenda Negra, Felipe II, Felipe V, Austrias y Borbones, la guerra de la Independencia, la historia cultural, los mitos de la historia de España... Muy pocos tienen su capacidad para reflexionar, ordenar, analizar, conceptualizar y proponer una visión amplia y llena de matices sobre el pasado y las interpretaciones historiográficas. A su laboriosidad inimitable se añade una dedicación sin límites en el asesoramiento de alumnos e investigadores e impulsando revistas, dosieres, seminarios o publicaciones colectivas. Una mínima correspondencia a su generosidad lo constituye este volumen a manera de ineludible agradecimiento
    corecore