Suitability of aquatic mosses for biomonitoring micro/meso plastics in freshwater ecosystems

Abstract Background Mesoplastics (5–25 mm) and microplastics (0.001–5 mm) are emerging pollutants of great concern. However, reliable methods of monitoring these types of plastic in river ecosystems have not yet been established. The goal of this work was to evaluate, for the first time, the suitability of Fontinalis antipyretica as a biomonitor of meso- and micro-plastics in rivers. With this aim, native samples of the moss and devitalized moss clones, held inside the bags, were compared for the uptake of fluorescent polystyrene particles under laboratory conditions, and for retention of plastic debris in the field, in sites close to wastewater treatment plants. Results In the laboratory experiment, the moss retained smaller microplastics, and a higher number of polystyrene meso and microplastics was counted in the moss bags than in the native moss. In the field study, the moss retained plastic debris chiefly in the form of fibres regardless of the capacity and flow rate of the wastewater treatment plants affecting each sampling site. The uniform morphology of moss clone seems to affect the retention of this type of pollutant. The FTIR analysis confirmed the particles entrapped by the moss bags as plastic, specifically polyethylene and polyamide type 6, among the most common plastic polymers detected in rivers. Conclusions The study findings highlighted the value of using uniform material, as the clone exhibited a greater accumulation efficiency with respect to the native moss. The mesh bags could act as selective filters and/or prevent the loss of adhering plastics. In the field, the bags favour plastic fibres retention despite the river flow. Finally, although FTIR is useful for the identification of plastic type, it is not very sensitive when small quantities of ground samples are used

Papel del logopeda en un centro gerontológico de estancias diurnas

[Resumen] El aumento de población anciana en nuestra sociedad es un hecho que ha provocado la aparición de nuevos recursos socio-sanitarios que cubran sus necesidades. El Centro Gerontológico de Estancias Diurnas es un servicio multidisciplinar diurno que se ocupa de la atención social y sanitaria, con actuación terapéutica y preventiva, de los mayores facilitando la vida laboral de las personas que se ocupan ordinariamente de su cuidado. Los centros de día deben proporcionar una atención integral debiendo, por tanto, estar constituidos por un equipo profesional multidisciplinar en el que la figura del logopeda esté presente desarrollando una labor específica. Parece, por tanto, interesante delimitar las funciones básicas a desempeñar, los trastornos más comunes susceptibles de intervención, así como, algunas directrices a tener en cuenta.[Abstract] The increase of the senior population in our society is an event that has provoked the appeareance of a new sort of social and sanitary recource, a structure that has to be concerned with the needs of this population. The gerontologic day-center is in brief a multidisciplinar service, that works during day time, treating the social and sanitary occupation of our elder with both therapeutic and preventive acts. This to provide a normal working life for the people who are usually taking care of these people. Day-centers have to answer these needs with a complete service, and for that reason they have to apile to a multidisciplinar staff in wich the speech-therapist develops a specific role. It seems though interesting to define the basic functions that a professional speech-therapist has to perform, such as the most common disorders capable of treatment and general intervention, as well derectives to bear in mind

Nitrogen fixation in the upwelling region off NW Iberia

Comunicación oralPicoplankton are the most abundant organisms in the ocean, often dominate planktonic biomass and primary production, and they could represent a substantial contribution to the global export of carbon. Nowadays, we have a limited understanding about the factors that control the picoplankton community structure. A recent analysis indicates that light and temperature are the main factors explaining Prochlorococcus and Synechococcus distributions, whereas nutrient concentrations play a minor role (Flombaum et al., PNAS 2013). Methodological difficulties to quantify mixing in the marine enviroments have motivated the use of indirect approaches to determine the input of nutrients into the euphotic zone, however, nutrient concentrations are not necessarily a proxy of nutrient supply. We present a large data set, including open-ocean and coastal regions, of simultaneous measurements of picoplankton abundance, temperature and irradiance, together with estimates of nutrient supply. The transport of nutrients across the nutricline was computed combining nutrient concentrations and small-scale turbulence observations collected with a microstructure profiler. Our preliminary results indicate that nutrient supply also plays a role in the distribution of functional groups of picoplankton in the ocean

Aplicación de Altas Presiones Hidrostáticas en jamón serrano: efecto sobre la intención de compra y las expectativas del consumidor.

La aplicación de nuevas tecnologías en productos tradicionales puede modificar su percepción entre los consumidores así como su valor de mercado. Por ello, es interesante evaluar no sólo la aceptación sino también el precio que estaría dispuesto a pagar el consumidor por un producto innovado. El objetivo de este trabajo es evaluar la respuesta del consumidor español ante la aplicación de altas presiones hidrostáticas en un producto tradicional como el jamón serrano. Para ello se realizó un estudio de consumidores (n=229) organizado en dos etapas. En la primera se evaluaron dos productos (jamón serrano tratado y no tratado con altas presiones hidrostáticas) en tres condiciones: cata a ciegas, expectativas y cata informada. En la segunda etapa, se determinó el precio que estaría dispuesto a pagar el consumidor por ambos productos (jamón serrano con y sin tratamiento por altas presiones) mediante subastas experimentales. No se observaron diferencias estadísticamente significativas en la aceptación ni en el precio que estaría dispuesto a pagar el consumidor por el jamón tratado frente al no tratado. Se puede concluir que el consumidor español acepta el tratamiento de altas presiones hidrostáticas en el jamón serrano, aunque no está dispuesto a pagar más por dicha innovación

TEMPORAL TRENDS OF HEAVY METAL CONCENTRATIONS IN BROWN MACROALGAE FROM COASTAL ENVIRONMENTS

Heavy metals are one of the major drivers of ecological changes in coastal ecosystems. Macroalgae are primary producers of great relevance for ecosystem structure and functioning in these environments, and play a key role in the trophic transfer of these contaminants in the food web. Here, we present the most extensive assessment until now (>3500 records) of heavy metal concentrations in brown macroalgae (Class Phaeophyceae) sampled between 1933 and 2020 worldwide. The study compiles this information from 420 peer reviewed articles to be used as a proxy of global long-term changes in metal concentrations. We report the first detailed multi-decadal time series of Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb and Zn in algae using generalized additive models (GAMs), confirming a significant decrease in metal contamination in the world’s coastal environments since ca. the 1970s for Pb (84% reduction), Zn (79%), Cd (77%) and Cu (72%), since the 1980s for Mn (75%) and Hg (65%), and since the 1990s for Cr (66%), Fe (64%) and Co (60%). Important environmental consequences for the whole aquatic ecosystem, even for human health, may be expected from these changes. The present results provide a building block for the overall evaluation of the status and trends of marine metal contamination, and will help researchers and policy makers to promote new legal regulations and environmental goals against pollution

Un estudio comparativo sobre el pensamiento profesional y la "acción docente" de los profesores de ciencias de Educación Secundaria. Parte II

Este artículo es la segunda parte de una investigación más amplia sobre el pensamiento del profesor (Martínez et al., 2001). En este caso el estudio gira en torno al análisis de las diferencias y similitudes entre dos muestras de profesores de ciencias de educación secundaria que difieren en sus años de docencia y en su trayectoria profesional, definida por la realización de cursos de formación permanente de alta cualificación científica y didáctica. En un primer apartado se analizan facetas relacionadas con la motivación y la satisfacción en la realización de su tarea, la manera de entender la formación del profesor y sus percepciones sobre diferentes factores profesionales. A continuación se aborda lo que «dicen hacer» en relación a aspectos curriculares referidos a contenidos, metodología y evaluación. A partir del análisis de las respuestas a los cuestionarios elaborados se plantean una serie de reflexiones que buscarían mejorar el «desarrollo profesional» de este colectivo de profesores.This article is a part of a wider research on secondary science teachers' beliefs. Through the use of a questionnaire data were obtained from 103 secondary science teachers in service with different degrees of experience. Analysis of data are discussed in terms of their implication in teacher training in service

Epitaxial growth of SrTiO3 films on cube-textured Cu-clad substrates by PLD at low temperature under reducing atmosphere

The growth of epitaxial {001} SrTiO3 (STO) on low-cost cube-textured Cu-based clad substrate at low temperature was carried out by means of pulsed laser deposition (PLD). STO film was deposited in one step under a reducing atmosphere (5% H2 and 95% Ar mixture) to prevent the oxidation of the metal surface. The optimization of PLD parameters leads to a sharpest biaxial texture at a temperature as low as 500 °C and a thickness of 500 nm with a (100) STO layer. The upper limit of highly textured STO thickness was also investigated. The maximum thickness which retains the best quality {001} texture is 800 nm, since the texture is preserved not only through the layer but also on the surface. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements showed that STO films are continuous, dense, and smooth with very low roughness (between 5 and 7 nm). This paper describes the development of STO layer by means of PLD in absence of oxygen throughout the process, suggesting an alternative and effective method for growing highly {001} textured STO layer on low-cost metal substrates

Short-term variability in the activity and composition of the diazotroph community in a coastal upwelling system

Today we know that diazotrophs are common and active in nitrogen (N) replete regions, however the factors controlling their distribution remain elusive. Previous studies in upwelling regions revealed that the composition of diazotrophs responded to changes in hydrodynamic forcing over seasonal scales. Here we used high-frequency observations collected during a 3-week cruise in the upwelling region off NW Iberia to describe changes in the activity and composition of diazotrophs over shorter temporal scales. The cruise started after a strong upwelling event followed by a few days of relaxation-downwelling, and soon after another upwelling pulse. Higher N2 fixation rates (2.2 ± 0.7 µmol m-3 d-1) were measured during relaxation-downwelling, when surface nitrate concentration was low. During the fertilization associated with the upwelling, N2 fixation dramatically decreased to 0.10 ± 0.09 µmol m-3 d-1. The comparison with nitrate consumption and diffusion confirmed the minor role of N2 fixation (<1%) as a source of new N for primary production. The unicellular cyanobacterium UCYN-A2 was the dominant diazotroph during the cruise. UCYN-A2 abundance was four times higher during relaxation-downwelling (4x104 copies L-1) compared to upwelling conditions (0.2x104 copies L-1), when the unusual Epsilonproteobacteria increased their relative abundance. These results indicate that diazotrophs can respond rapidly to changes in the environment, and point out to the availability of N as a key factor controlling the activity, composition and distribution of diazotrophs in eutrophic regions

¿Qué pensamiento profesional y curricular tienen los futuros profesores de ciencias de Secundaria?

This article is a part of a wider research on secondary science teachers' beliefs. Through the use of a questionnaire data were obtained from 211 secondary science teacher candidates. Analyses of data are discussed in terms of their implication in science teacher education

The ALHAMBRA survey: Accurate merger fractions by PDF analysis of photometric close pairs

Our goal is to develop and test a novel methodology to compute accurate close pair fractions with photometric redshifts. We improve the current methodologies to estimate the merger fraction f_m from photometric redshifts by (i) using the full probability distribution functions (PDFs) of the sources in redshift space, (ii) including the variation in the luminosity of the sources with z in both the selection of the samples and in the luminosity ratio constrain, and (iii) splitting individual PDFs into red and blue spectral templates to deal robustly with colour selections. We test the performance of our new methodology with the PDFs provided by the ALHAMBRA photometric survey. The merger fractions and rates from the ALHAMBRA survey are in excellent agreement with those from spectroscopic work, both for the general population and for red and blue galaxies. With the merger rate of bright (M_B <= -20 - 1.1z) galaxies evolving as (1+z)^n, the power-law index n is larger for blue galaxies (n = 2.7 +- 0.5) than for red galaxies (n = 1.3 +- 0.4), confirming previous results. Integrating the merger rate over cosmic time, we find that the average number of mergers per galaxy since z = 1 is N_m = 0.57 +- 0.05 for red galaxies and N_m = 0.26 +- 0.02 for blue galaxies. Our new methodology exploits statistically all the available information provided by photometric redshift codes and provides accurate measurements of the merger fraction by close pairs only using photometric redshifts. Current and future photometric surveys will benefit of this new methodology.Comment: Submitted to A&A, 15 pages, 15 figures, 6 tables. Comments are welcome. Close pair systems available at https://cloud.iaa.csic.es/alhambra/catalogues/ClosePairs