8,061 research outputs found
A new self-organizing neural gas model based on Bregman divergences
In this paper, a new self-organizing neural gas model that we call Growing Hierarchical Bregman Neural
Gas (GHBNG) has been proposed. Our proposal is based on the Growing Hierarchical Neural Gas (GHNG) in which Bregman divergences are incorporated in order to compute the winning neuron. This model has been applied to anomaly detection in video sequences together with a Faster R-CNN as an object detector module. Experimental results not only confirm the effectiveness of the GHBNG for the detection of anomalous object in video sequences but also its selforganization
capabilities.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Two RNA-binding motifs in eIF3 direct HCV IRES-dependent translation.
The initiation of protein synthesis plays an essential regulatory role in human biology. At the center of the initiation pathway, the 13-subunit eukaryotic translation initiation factor 3 (eIF3) controls access of other initiation factors and mRNA to the ribosome by unknown mechanisms. Using electron microscopy (EM), bioinformatics and biochemical experiments, we identify two highly conserved RNA-binding motifs in eIF3 that direct translation initiation from the hepatitis C virus internal ribosome entry site (HCV IRES) RNA. Mutations in the RNA-binding motif of subunit eIF3a weaken eIF3 binding to the HCV IRES and the 40S ribosomal subunit, thereby suppressing eIF2-dependent recognition of the start codon. Mutations in the eIF3c RNA-binding motif also reduce 40S ribosomal subunit binding to eIF3, and inhibit eIF5B-dependent steps downstream of start codon recognition. These results provide the first connection between the structure of the central translation initiation factor eIF3 and recognition of the HCV genomic RNA start codon, molecular interactions that likely extend to the human transcriptome
Alteraciones de la superficie del cuerpo vertebral en una población medieval de Logroño (s. XI y XII)
X Congreso Nacional de Paleopatología. Univesidad Autónoma de Madrid, septiembre de 200
Biogeographical boundaries, functional group structure and diversity of rocky shore communities along the Argentinean coast
We investigate the extent to which functional structure and spatial variability of intertidal communities coincide with major biogeographical boundaries, areas where extensive compositional changes in the biota are observed over a limited geographic extension. We then investigate whether spatial variation in the biomass of functional groups, over geographic (10′s km) and local (10′s m) scales, could be associated to species diversity within and among these groups. Functional community structure expressed as abundance (density, cover and biomass) and composition of major functional groups was quantified through field surveys at 20 rocky intertidal shores spanning six degrees of latitude along the southwest Atlantic coast of Argentina and extending across the boundaries between the Argentinean and Magellanic Provinces. Patterns of abundance of individual functional groups were not uniformly matched with biogeographical regions. Only ephemeral algae showed an abrupt geographical discontinuity coincident with changes in biogeographic boundaries, and this was limited to the mid intertidal zone. We identified 3–4 main ‘groups’ of sites in terms of the total and relative abundance of the major functional groups, but these did not coincide with biogeographical boundaries, nor did they follow latitudinal arrangement. Thus, processes that determine the functional structure of these intertidal communities are insensitive to biogeographical boundaries. Over both geographical and local spatial scales, and for most functional groups and tidal levels, increases in species richness within the functional group was significantly associated to increased total biomass and reduced spatial variability of the group. These results suggest that species belonging to the same functional group are sufficiently uncorrelated over space (i.e. metres and site-to-site ) to stabilize patterns of biomass variability and, in this manner, provide a buffer, or “insurance”, against spatial variability in environmental conditions
Concentrations of total phenols and antioxidant activity in apple do not differ between conventional and organic orchard Management
Reprint Address: Yuri, JA (reprint author), Talca Univ, Agr Sci Fac, Pomaceas Ctr, Talca, Chile.The apple is one of the most widely consumed fresh fruits in the world. It constitutes a major contribution of phytochemical compounds to the diet, which are associated with a reduced risk to develop degenerative diseases. The main objective of this study was to evaluate the effects of conventional and organic management of apple cultivation, the stage of development and sunburn damage on polyphenol concentrations, antioxidant activity and pigments in three apple cultivars. Two experiments were carried out during the 2009/2010 season to study (1) the effect of the type of management and the development stage of the fruit during the season on the concentration and content of total and specific phenolics, antioxidant activity in the whole fruit, and pigments (chlorophylls, carotenoids and anthocyanins) in the peel of cvs. Gala (Galaxy and Brookfield), Granny Smith and Fuji (Raku Raku and Stripped) and (2) the effect of the type of management and the presence of sunburn at harvest on phenolics concentrations and antioxidant activity in both the whole fruit and peel, as well as pigments in peel, in two cultivars. Phenolics concentrations and antioxidant activity increased in the First weeks of fruit development and then decreased until harvest. The concentration of chlorophyll and carotenoids tended to decrease throughout the season, while anthocyanin concentration increased. In the case of tissue damaged by sunburn, phenolics concentrations and antioxidant activity were higher in damaged fruit, while changes in pigment concentrations varied according to the cultivar. The practices of conventional and organic management did neither influence significantly phenolics and pigments concentrations and antioxidant activity, except at certain stages of fruit development
Temporal study of natural populations of Heterorhabditid and Steinernematid nematodes in horticultural crop soils
La dynamique des populations de nématodes entomopathogènes dans des sols horticoles a été étudiée par des prélèvements mensuels en huit sites de Catalogne (nord-est de l'Espagne) pendant 14 mois. Ces nématodes entomopathogènes ont été détectés dans six des huit sites et ont continué à l'être quels qu'aient été les traitements agricoles pratiqués sur ces sites. Pendant cette étude, les sites ont été labourés, détruisant ainsi l'habitat naturel des nématodes, puis laissés en jachère pendant plusieurs mois, sans que la présence des nématodes n'en paraisse affectée. Cependant, une influence saisonnière peut être observée, la présence des nématodes étant plus faible pendant les mois d'été où la température est élevée. Cette influence saisonnière apparaît également affecter la répartition verticale des nématodes qui migrent vers les couches plus profondes du sol, vraisemblablement pour éviter les effets néfastes de la température et du manque d'humidité. Les résultats de cette étude montrent que les populations naturelles de nématodes entomopathogènes sont capables de persister et de survivre dans le sol pendant de longues périodes en s'adaptant aux conditions fluctuantes et adverses de leur habitat naturel. (Résumé d'auteur
Conservation biogeography of ecologically interacting species: The case of the Iberian lynx and the European rabbit
Aim
To relate the recent Iberian lynx decline to changes in the distribution of the
European rabbit after the haemorrhagic disease outbreak of 1989. As Iberian rabbits
evolved in two geographically separated lineages, being the recent lynx range practically
restricted to the southwestern lineage, we also test if differential range dynamics
exists for these lineages, with the consequent implications for lynx conservation and
reintroduction planning
Infraestructura de datos espaciales en medio ambiente y acceso a la información ambiental en Andalucía. El canal de la red de información ambiental de Andalucía.
La Consejería de Medio Ambiente de la Junta de Andalucía ha puesto en marcha un sistema para poder cumplir adecuadamente los requisitos derivados de la normativa vigente en dos vertientes que están muy relacionadas: la del acceso a la información ambiental y la de las Infraestructuras de Datos Espaciales. Ambas vertientes, que vienen definidas por sendas Directivas, han condicionado la solución establecida que pasa por la creación mediante el desarrollo normativo adecuado de un instrumento, la Red de Información Ambiental de Andalucía (REDIAM). Esta red se ha dotado de una plataforma en entorno web, el Canal de la Red de Información Ambiental de Andalucía, en la que confluyen elementos constitutivos de una Infraestructura de Datos Espaciales (IDE) con otros de obtención y acceso al dato como es el de de solicitud de información ambiental o la descarga directa, y con elementos de navegación que pretenden facilitar al público en general el acceso a este conjunto de servicios y productos. Puesto en explotación el 29 de enero de 2009, hoy podemos hacer balance del uso que ha registrado en su primer año.The Ministry of Environment of the Junta de Andalucía has launched a system to carry out the requirements under current regulations in two areas which are closely related: access to environmental information and Spatial Data Infrastructures. Both sides, which are defined by EU Directives, have conditioned the solution through the developing an appropriate regulatory instrument, the Environmental Information Network of Andalusia (REDIAM). This network has set up a web-based platform, the Andalusian Environmental Information Network Channel, which combines elements of a Spatial Data Infrastructure (SDI) with other elements of data collection and access like the environmental information request or direct download, and navigation elements that are intended to facilitate the general public access to the package of services and products. Having been put into operation on January 29, 2009, today we can assess the use it has registered in its first year
Identification of the water stress level in olive trees during pit hardening using the trunk growth rate indicator.
Water scarcity is generating an increasing interest in deficit irrigation scheduling. The trunk diameter fluctuations are daily cycles that have been suggested as tools for irrigation scheduling. The trunk growth rate (TGR) was suggested as the best indicator for olive trees during pit hardening. The aim of this work is to clarify how the TGR could be used to identify water stress levels. The experiment was performed during the 2017 season, in a commercial, super-high-density orchard in Carmona (Seville, Spain). Four different irrigation treatments were performed according to midday stem water potential values and TGR. The data obtained were very variable and both indicators presented a wide range of water status throughout the season. The maximum trunk diameter data clearly showed the pattern of the trees water status but the comparison between treatments and the identification of the water stress level was not possible. The average TGR was linked to the midday stem water potential, but with a minimum amount of data. Irrigation scheduling based on the average TGR was difficult because of the great increases in some daily TGR values. For clarity, the pool of data was grouped by midday stem water potential. These water stress levels were characterized using the weekly frequency of TGR values. The increase of water stress reduced the frequency of values between -0.1 and 0.3mm day-1 from 60% to less than 25%. Moderate water stress levels increased the percentage of values lower than -0.3mm day-1 from 7% to 37%. The most severe water stress conditions increased the TGR values between -0.3 and -0.1mm day-1 from 16% up to 22%.IRNASINSTITUTO DE LA GRASACSI
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