Bases para la construcción tecnológica sostenible: aplicación en un edificio plurifamiliar

En la actualidad, y cada vez más a menudo, se están aplicando criterios de sostenibilidad y bioclimatismo tanto en edificios residenciales como en edificios públicos. La sociedad está en proceso de aceptación de los nuevos métodos tecnológicos aplicados a la construcción moderna, los cuales buscan un ahorro económico, energético y de tiempos de ejecución. Todo esto, consiguiendo que la comodidad de las personas que deban habitar dichas construcciones no se vea afectada, es decir, conservando o incluso mejorando su calidad de vida y sensación de bienestar térmico, ya sea en el interior de sus viviendas o de centros públicos destinados cualquier tipo de actividad. El sector de la construcción es uno de los que genera mayor impacto ambiental, puesto que consume elevados índices de recursos naturales, tales como madera, minerales, agua y combustibles fósiles. Además, aportan grandes cantidades de emisiones de gases de efecto invernadero y contaminantes, tanto en fase de ejecución como durante la vida útil de las construcciones. La condición sine qua non para una correcta implementación de la construcción sostenible es el compromiso con la conservación del medioambiente y la adaptación de las edificaciones al mismo para tratar de alterar su estado natural en la menor medida posible. Para terminar de convencer de estas ideas a aquellos que aun se muestren escépticos, se plantean como objetivos demostrar con datos numéricos el ahorro económico, la reducción de las emisiones de CO2 y la disminución del tiempo de ejecución que supondría construir un edificio de viviendas plurifamiliar con un sistema modular de paneles portantes semiprefabricados de hormigón armado para fachadas, forjados de losa alveolar prefabricada y aparcamiento sobre rasante con ventilación natural en lugar del sistema de construcción húmeda tradicional de estructuras de hormigón in situ, cerramientos de fábrica de ladrillo, forjados reticulares y aparcamiento bajo rasante con ventilación mecánica. Para ello, se emplean la base de datos BEDEC disponible en la web del ITEC así como los ejemplares más recientes de las revistas EME2 y el Boletín Económico de la Construcción. Confirmando la teoría, se obtienen unos resultados muy positivos en las tres comparativas y, por eso, complementamos el proyecto presentando un modelo de diseño urbano sostenible para el distrito del 22@ de Barcelona, basado en la reproducción consecutiva del proyecto y habilitando zonas verdes y vías de transito que ayuden a ordenar de forma clara y lógica tanto a vehículos como a peatones

Time series are critical to understand microbial plankton diversity and ecology

International audienceHow diverse are marine planktonic protist communities? How much seasonality do they exhibit? For a very long time, these two old and challenging questions in the field of plankton ecology could be addressed only for large-size protist species, based on cell counting under the microscope. The recent application of molecular techniques, notably massive marker-gene amplicon sequencing approaches (metabarcoding), has allowed investigating with unprecedented level of resolution the small-sized (<20 µm) planktonic eukaryotes too. An amazing diversity of these tiny organisms has been unveiled but details about their temporal dynamics remain much more elusive. In a From the Cover article in this issue of Molecular Ecology, Giner et al. (2019) introduce a new Recurrence Index (RI) to specifically look for seasonality in time-series metabarcoding data. They inspected the temporal dynamics of all operational taxonomic units (OTUs) in a rich sequence data set of pico- and nanoplanktonic eukaryotes in samples collected monthly during 10 years. Although most OTUs did not show seasonality, some abundant ones did, which explains why some averaging methods can find seasonality at the less detailed level of whole planktonic communities. Not surprisingly, the very complex small-sized eukaryotic plankton communities are composed of organisms with miscellaneous temporal dynamics

Evaluation of Enzyme Additives on the Nutritional Use of Feeds with a High Content of Plant Ingredients for Mugil cephalus

The Mugilidae are a group of fish with a great interest for aquaculture due to their omnivorous profile, rapid growth, and resistance to environmental variations. The selection of feed ingredients for these species is currently focused on an extensive use of plant by-products, with this being limited by their content in anti-nutritive factors (mainly phytate and non-starch polysaccharides; NSPs). Nevertheless, specific enzymes can be used to counteract some of those negative effects. In the present study, the effect of pretreating two high-plant feeds with a mixture of enzymes (glucanases + phytase) on the digestive use of protein and phosphorus by juvenile mullets (Mugil cephalus) was assessed using both in vitro and in vivo assays. The enzymatic treatment significantly modified the potential bioavailability of some nutrients, such as a reduction of sugars, pentoses, and phytic phosphorus. Also, it increased the digestibility of protein in one of the feeds but reduced that of phosphorus in both of them. The potential usefulness of enzyme treatment and the information provided by the two types of assays are discusse

Diversity and Vertical Distribution of Microbial Eukaryotes in the Snow, Sea Ice and Seawater Near the North Pole at the End of the Polar Night

Our knowledge about the microorganisms living in the high Arctic Ocean is still rudimentary compared to other oceans mostly because of logistical challenges imposed by its inhospitable climate and the presence of a multi-year ice cap. We have used 18S rRNA gene libraries to study the diversity of microbial eukaryotes in the upper part of the water column (0–170 m depth), the sea ice (0–1.5 m depth) and the overlying snow from samples collected in the vicinity of the North Pole (N88°35′, E015°59) at the very end of the long polar night. We detected very diverse eukaryotes belonging to Alveolata, Fungi, Amoebozoa, Viridiplantae, Metazoa, Rhizaria, Heterokonta, and Telonemia. Different alveolates (dinoflagellates and Marine Alveolate Groups I and II species) were the most abundant and diverse in gene libraries from water and sea ice, representing 80% of the total number of clones and operational taxonomic units. Only contaminants and/or species from continental ecosystems were detected in snow, suggesting wind- and animal- or human-mediated cosmopolitan dispersal of some taxa. By contrast, sea ice and seawater samples harbored a larger and more similar inter-sample protist diversity as compared with snow. The North Pole was found to harbor distinctive eukaryotic communities along the vertical gradient with an unparalleled diversity of core dinoflagellates, largely dominant in libraries from the water column, as compared to other oceanic locations. In contrast, phototrophic organisms typical of Arctic sea ice and plankton, such as diatoms and prasinophytes, were very rare in our samples. This was most likely due to a decrease of their populations after several months of polar night darkness and to the presence of rich populations of diverse grazers. Whereas strict phototrophs were scarce, we identified a variety of likely mixotrophic taxa, which supports the idea that mixotrophy may be important for the survival of diverse protists through the long polar night

Misconceptions in Science

peer reviewedAbstract Disagreement in science exists in a variety of strengths, from doubt-raising articles and issues of non-reproducibility up to raging disputes and major controversies. An often-latent form of disagreement consists of misconceptions whereby false ideas are held that run contrary to what is commonly accepted as knowledge. Misconceptions have been the focus of much research in education science and psychology. Here we draw attention to misconceptions that may arise in the very practice of science. We highlight formal features that can be used to characterize misconceptions and distinguish them from controversies, in addition to how they relate to knowledge creation

Maturases and Group II Introns in the Mitochondrial Genomes of the Deepest Jakobid Branch

Ophirinina is a recently described suborder of jakobid protists (Excavata) with only one described species to date, Ophirina amphinema. Despite the acquisition and analysis of massive transcriptomic and mitogenomic sequence data from O. amphinema, its phylogenetic position among excavates remained inconclusive, branching as sister group either to all Jakobida or to all Discoba. From a morphological perspective, it has not only several typical jakobid features but also unusual traits for this group, including the morphology of mitochondrial cristae (sac-shaped to flattened-curved cristae) and the presence of two flagellar vanes. In this study, we have isolated, morphologically characterized, and sequenced genome and transcriptome data of two new Ophirinina species: Ophirina chinija sp. nov. and Agogonia voluta gen. et sp. nov. Ophirina chinija differs from O. amphinema in having rounded cell ends, subapically emerging flagella and a posterior cell protrusion. The much more distantly related A. voluta has several unique ultrastructural characteristics, including sac-shaped mitochondrial cristae and a complex “B” fiber. Phylogenomic analyses with a large conserved-marker dataset supported the monophyly of Ophirina and Agogonia within the Ophirinina and, more importantly, resolved the conflicting position of ophirinids as the sister clade to all other jakobids. The characterization of the mitochondrial genomes showed that Agogonia differs from all known gene-rich jakobid mitogenomes by the presence of two group II introns and their corresponding maturase protein genes. A phylogenetic analysis of the diversity of known maturases confirmed that the Agogonia proteins are highly divergent from each other and define distant families among the prokaryotic and eukaryotic maturases. This opens the intriguing possibility that, compared to other jakobids, Ophirinina may have retained additional mitochondrial elements that may help to understand the early diversification of eukaryotes and the evolution of mitochondria.We thank Dr. Sergey A. Karpov (Zoological Institute RAS) and Dr. Denis V. Tikhonenkov (IBIW RAS) for their helpful discussions on the ultrastructural observations, and Dr. Hwan Su Yoon (Sungkyunkwan University) for the mitochondrial marker alignments. This work was supported by the European Research Council (ERC) Advanced Grants “Protistworld” and “Plast-Evol” (322669 and 787904, respectively) and the Horizon 2020 research and innovation program under the Marie Skłodowska-Curie ITN project SINGEK H2020-MSCA-ITN-2015-675752 (http://www.singek.eu/). G.T. was supported by the 2019 BP 00208 Beatriu de Pinos-3 Postdoctoral Program (BP3; 801370).Peer ReviewedPostprint (published version

Diseño y propiedades psicométricas del AVACO-EVADIE. Cuestionario para la evaluación de la atención a la diversidad como dimensión educativa en las instituciones escolares

El presente artículo muestra el proceso seguido para diseñar e identificar las propiedades psicométricas del instrumento de evaluación del constructo Atención a la Diversidad como variable de contexto. Para ello, se ha comenzado con una pequeña revisión de los instrumentos utilizados para recoger información sobre la diversidad tanto cultural como social, lingü.stica o en capacidades. A continuación y, partiendo de una clasificación de los distintos enfoques teóricos, se ha construido un primer instrumento, apostando por un enfoque inclusivo. Posteriormente se procede a una validación por expertos. Tras la validación se toma la decisión de subdividir el instrumento original en cuatro instrumentos, uno por audiencia encuestada y por último al pilotaje del mismo. El análisis de la fiabilidad del instrumento nos lleva a la conclusión de que se trata de un cuestionario fiable para recoger información acerca de como afrontan los centros la Atención a la Diversidad.