Introducing the concept of infinite series: Preliminary analyses of curriculum content and pedagogical practice

Introducing the concept of infinite series: preliminary analyses of curriculum content and pedagogical practice

First order formulation of unimodular gravity

First order Lagrangians for the Weyl invariant formulation of unimodular gravity are proposed. Several alternatives are examined; in some of them, first and second order are equivalent in a certain gauge onlyThis work has been partially supported by the European Union FP7 ITN INVISIBLES (Marie Curie Actions, PITN- GA-2011- 289442) and (HPRN-CT-200-00148), COST action MP1405 (Quantum Structure of Spacetime), COST action MP1210 (The String Theory Universe) as well as by FPA2012-31880 (MINECO, Spain) and S2009ESP-1473 (CA Madrid). The authors acknowledge the support of the Spanish MINECO Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-024

Determination of the Chiral Couplings L_10 and C_87 from Semileptonic Tau Decays

Using recent precise hadronic tau-decay data on the V-A spectral function, and general properties of QCD such as analyticity, the operator product expansion and chiral perturbation theory, we get accurate values for the QCD chiral order parameters L_10^r(M_rho) and C_87^r(M_rho). These two low-energy constants appear at order p^4 and p^6, respectively, in the chiral perturbation theory expansion of the V-A correlator. At order p^4 we obtain L_10^r(M_rho) = -(5.22\pm 0.06)10^{-3}. Including in the analysis the two-loop (order p^6) contributions, we get L_10^r(M_rho) = -(4.06\pm 0.39)10^{-3} and C_87^r(M_rho) = (4.89\pm 0.19)10^{-3}GeV^{-2}. In the SU(2) chiral effective theory, the corresponding low-energy coupling takes the value \overline l_5 = 13.30 \pm 0.11 at order p^4, and \overline l_5 = 12.24 \pm 0.21 at order p^6.Comment: 17 pages, 3 figures, v2: Added reference, published versio

Andamios porosos (apatita/colágeno) de origen marino para aplicaciones biomédicas

1 póster presentado en las III Xornadas de Investigación BioIntegraSaúde 2015, Vigo 16 xuño 2015.-- E. López-Senra ... et al.FP7/REGPOT-2012-2013.1 (nº 316265, BIOCAPS); UE-INTERREG 2011-1/164 MARMED; Ministerio de Ciencia e Innovación (Project MAT2010-18281)Peer reviewe

Seasonal inputs of polyethoxylated compounds to a Mediterranean coastal lagoon through surface watercourses

Synthetic surfactants are among the chemicals that are produced and consumed in the largest volumes in the world (more than 10 million tons per year), due to their variety of applications, mainly as key ingredients in detergents and cleaners but also as additives in paints, pesticides, personal care products, etc. In spite of the high removal efficiences of surfactant residues in sewage treatment plants (STP), significant amounts of these chemicals reach aquatic ecosystems via direct discharges of treated or non-treated wastewaters, or indirect discharges through rivers, where they are present dissolved or associated with particulate material. Therefore, particular attention has been given to the environmental analysis of anionic and non-ionic surfactants (90% of the overall production. Our main objective in this work was to detect the presence and compare the distribution of the most world-wide used non-ionic (alcohol polyethoxylates, AEOs, and nonylphenol polyethoxylates, NPEOs) surfactants, and an important group of nonionic synthetic water-soluble polymers of ethylene oxide, polyethylene glycols (PEGs), which are also used in a wide range of applications (e.g., antifreeze agents, cosmetics) as well as the main precursors / degradation products of AEOs, in waters and sediments from Mar Menor Lagoon (SE Spain). Under our knowledge, some of the data shown here are among the first even reported on the environmental distribution of PEGs in aquatic systems

Cryopreservation of embryogenic cell suspensions of the Spanish grapevine cultivars ‘Albariño’ and ‘Tempranillo’

Embryogenic cell suspensions of two elite Spanish grapevine cultivars (‘Albariño’ and ‘Tempranillo’) were successfully cryopreserved by encapsulation-dehydration. The method implied the encapsulation of cells in alginate beads, subsequent culture in liquid medium with 1 M sucrose for 4 days, and desiccation for 2-4 h in the flow of a laminar-flow bench, before immersing in liquid nitrogen. With this simple method, up to 50 % of cell viability in the cryopreserved beads was measured (using the triphenyl tetrazolium method), which corresponded to vigorous growth of 100 % of beads after culture on semi-solid medium. The cryopreserved encapsulated cells were successfully used for initiation of new cell suspensions and their embryogenic capacity was studied. This cryopreservation method is an advance to store ready-to-use competent embryogenic tissue for grapevine genetic transformation projects