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L1 and L2 differences in the acquisition of information structure: examining an interface-based account
Performance-Based Specifications: Exploring When They Work and Why
There is extensive research and attention on innovation and sustainable public procurement (SPP) in the European Union at present, with the 2014 revision of the Procurement Directives, the Innovation Union strategy and other European Union policy initiatives. This report seeks to contribute to this discussion through the investigation of the use of performance based specifications (PBSs) in public procurement in the European Union and the United States. The report outlines the benefits and limitations of the use of PBSs, even in the most "progressive" public procurement environments, such as the Netherlands, particularly around their ability to support sustainable development goals and deliver environmental benefits for a procuring authority, such as energy and resource efficiency. Additionally, this report aims to identify the sectors in which the enabling conditions for the successful use of PBSs in public procurement are in place and to understand what policies and regulations are needed to promote the use of PBSs in public tenders and public procurement framework agreements
Urban space and its transformation in two Spanish Mediterranean cities: Alicante and Murcia
During last two decades all Spanish Mediterranean cities have increased their surface and, in consequence, their urban public space is nowadays greater than it was before. Not only the amount of public space has increased, but also the role that public space has now is not anymore the same, especially in middle urban areas. Alicante and Murcia are good examples of the group of cities where the population growth and sprawl impact have had an important role in the transformation of the cities over the last two decades. The aim of this paper is to study, in those two cities, how public space has been transformed in the existing city and designed in new areas. Four important processes can be underlined considering the use and features of urban public space: firstly, city centre public spaces have maintained their relevant use but their design have been updated to currently activities; secondly, the implementation of new public transport - light metro or tramway- has renewed public space in the city centre and in the periphery; thirdly, the change of population habits that include activities that previously took place in public urban spaces and recently have been moved to private places related to shopping centres; and fourthly, the lack of quality public spaces in new suburbs based on low density houses and where all means of transport are private cars
Ecological Structure of Estaurine Fish Communities: Habitat Linkages Among Dominant Species Groups in Terminos Lagoon, Mexico.
Terminos Lagoon in the southern Gulf of Mexico has 5 ecological subsystems: (1) fluvial lagoon systems (FLS) with permanent river discharge, low salinity, high turbidity and nutrients. (2) Central basin (CB) between marine and river conditions, intermediate salinity and variable transparency. (3) Inner littoral of Carmen Island (ILCI) with strong marine influence, high transparency and extensive seagrass meadows. (4) Carmen inlet (Estero Pargo, ESP) with a net outflow of water and high turbidity. (5) Puerto Real inlet (PR) with a net inflow of waters, high transparency and seagrasses. During a 15-month sampling, 13,691 individuals of 79 different species were collected in 264 trawls. Mandamango catfish, checkered puffer, silver perch, hardhead catfish and sea bream accounted for 63% of the total capture. Seventeen species accounted for 90% of all individuals, and 25 species had less than 5 individuals. Biomass and density peaked during the rainy and norte seasons at ESP, ILCI and FLS; and during the dry season at CB. Small individuals were captured in ESP and the FLS, and larger sizes in CB and ILCI, suggesting the role of the lagoon as nursery and feeding grounds. Salinity in ESP, and Secchi depth in the ILCI were the environmental controlling factors. In the FLS, the community ecology is controlled by numerous factors that limit the patterns of diversity and abundance. The dominant species were classified as: (1) resident species: (a) typically estuarine with reproduction in the lagoon and, (b) typically estuarine with spawning areas located in the inner shelf; (2) Seasonal species with a marked periodicity; and (3) Occasional visitors with limited spatial distribution. Fish usage for PR and at ESP showed 53% of common species for both areas, 30% exclusive to ESP and 15% to PR. Adults enter through PR in the fall, and spawn near-shore in the vicinity of the inlet. During the dry season, the density and biomass (juveniles and pre-adults) was highest in the ILCI and ESP areas coincidental to the highest primary production and the most rapid growth period of their life history
The Late Jurassic pterosaurs from northern Patagonia, Argentina
Records of flying Jurassic reptiles are very scarce in the Southern Hemisphere. Upper Jurassic pterosaurs have been discovered in marine Tithonian sediments of the Vaca Muerta Formation, in the Neuquén Basin, Patagonia, Argentina. Only four specimens are known so far: the first from Arroyo Picún Leufú, and the other three from the lithographic limestones of Los Catutos. Here, we update knowledge of Late Jurassic pterosaurs from northwest Patagonia. We revise the diagnosis and description of a previously described pterodactyloid, which is named as a new genus and species, Wenupteryx uzi. This small-sized pterosaur shows affinities with Euctenochasmatia or Archaeopterodactyloidea, and represents the most complete Jurassic pterosaur so far known from the Southern Hemisphere. We also report a recent finding suggesting that the new specimen belongs to a new species of pterodactyloid pterosaur. These records show that at least three different taxa of pterosaurs coexisted in the Neuquén Basin: Herbstosaurus, Wenupteryx and a more derived pterodactyloid that represents the largest pterosaur known from the Upper Jurassic of Gondwana.Fil: Codorniú Dominguez, Laura Susana. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias FÃsico Matemáticas y Naturales. Departamento de Geologia, Argentina;Fil: Brandoni, Zulma Nelida. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División PaleontologÃa Vertebrados; Argentin
Desarrollo de un Sistema de Identificación de Objetos en Video
En la actualidad los sistemas de identificación de objetos en imágenes en video han sido utilizados en múltiples campos de investigación. Estos sistemas permiten resolver diversos problemas dependiendo del área de aplicación. Los algoritmos existentes en el estado del arte permiten detectar objetos con diferente precisión, esto de acuerdo a la calidad de las imágenes y video, color, pre procesamiento y tipo de algoritmo seleccionado. El presente trabajo propone e implementa un sistema de identificación de objetos en video. Para resaltar el desempeño de los algoritmos bajo un problema en particular se implementan los algoritmos para resolver el problema.CONACyT, no. de cuenta: 092102
Intracellular characterization of Gag-GFP VLP production upon PEImediated transient transfection of HEK 293 cells
Transient Gene Expression is a fast, flexible, and cost-effective approach to produce high-quality products that circumvents the time and cost required for the generation of stably transfected cell lines. However, the levels of recombinant protein produced by TGE, tend to be significantly lower than those of stable cell lines. Despite the continued interest in transient gene expression approaches, little is known about the transfection process at intracellular level, particularly for complex products such as VLPs. The kinetics of PEI-mediated transient transfection was studied with the aim of characterizing and understanding the complete process leading to VLP generation, and identifying important events to drive process improvement. For this purpose, DNA/PEI polyplexes were tracked using Cy3 DNA staining and the production of Gag-GFP VLPs was monitored by flow cytometry, confocal microscopy, and fluorometry. Flow cytometry and confocal microscopy assays show that using a standard transfection protocol DNA:PEI polyplexes interact with the cell membrane from time point zero. A linear increase in transfection efficiency is observed until 60 minutes of contact between cells and polyplexes. No change in transfection efficiency (percentage of GFP positive cells) or VLP production levels is obtained when additional contact time is allowed, reaching a maximum transfection efficiency of 60% and VLP production of 10x109 VLPs/mL harvested at 48 hours post transfection (hpt). After 1.5 hpt, polyplexes are detected in the cytoplasm of transfected cells and reach the nucleus around 4 hpt. Of note, all cells show the presence of DNA/PEI complex in the cytoplasm after transfection but only a fraction of cells express the fluorescent Gag protein. By flow cytometry analysis of isolated nuclei, it was determined that polyplexes are only present in 60% of the nuclei at 6 hpt (concomitant with the GFP expressing cells), suggesting that the entrance of polyplexes to the nucleus is one of the limiting steps of the transfection process. After 10 hpt, GFP fluorescence is detected homogenously inside the cells, but generalized budding of VLPs is not observed until 48 hpt. As mentioned before, a unique population of cells Cy3+ (with a polyplex inside) appears from the very beginning of the transfection. A new population of cells that do not contain any polyplex inside (Cy3-) and do not express the protein (GFP-) appears at 24 hpt suggesting plasmid loss after this time point. The VLP production kinetics was also studied, observing that fluorescence in the supernatant is always 40% less than total fluorencense (supernatant plus pellet). Maximum VLP levels in the cell culture supernatant, while keeping cell culture viability still high, are observed at 72 hpt, which was determined to be the optimal harvest time. Three bottlenecks in VLP production could be identified in this work: polyplexes entry into the nucleus, plasmid loss during the production phase and VLP buddin
Presbyphagia and dysphagia in old age
Although presbyphagia is a clinically relevant problem among elderly population, possibly leading to dysphagia in old age, it remains a still underestimated health condi-tion. The present review analyzes swallow-ing related anatomical and functional changes during aging, both in healthy peo-ple and in those affected by dysphagia. First of all, dysphagia in old people must not be confused with presbyphagia. To distinguish these two different conditions, a correct def-inition of both should be considered. Subsequently, a comprehensive evaluation including instrumental analysis should be carried out. The aim of this narrative review is to analyze the current knowledge of this clinical condition and to provide the state of art to clinicians. A systematic PubMed research on dysphagia in the elderly was conducted and most relevant and most recent references were manually screened and selected. The aim of a correct diagnosis is to enable the choice of a correct interven-tion in order to prevent and treat complica-tions of dysphagia, such as ab ingestis pneumonia and malnutrition. Moreover, the assessment, diagnosis and therapy of dys-phagia/presbyphagia should include the intervention of different specialists
Nem isto, nem aquilo: processos formativos em alfabetização
This study was conducted in order to introduce a reflection of acts of study and
practice aimed at the area of literacy. Developing from my memory about my
experience being literate, such as the activities developed in the Teaching Initiation
Program and internships.The theme proposal came up with my insertion as a PIBID
scholarship holder, which allowed an intense dialogue with the authors. The central
focus is to develop an analysis of literacy methods focused on this or that,
concluding then that it is necessary to understand it as a plural practice, in which
literacy must be valued. For this, the study methodology will be the experience report
linked to a bibliographical research.Este estudo foi realizado buscando apresentar uma reflexão de atos de
estudo e prática voltados a área da alfabetização. Desenvolvendo desde minha
memória sobre minha vivência sendo alfabetizada, como as atividades
desenvolvidas no Programa de Iniciação à Docência e estágios. A proposta de tema
surgiu com a minha inserção como bolsista do PIBID, que permitiu um diálogo
intenso com os autores. O foco central é desenvolver uma análise sobre os métodos
de alfabetização voltada em ou isso ou aquilo, concluindo então que é preciso
entendê-la como uma prática plural, na qual deve-se valorizar o alfaletrar. Para isso,
a metodologia de estudo será o relato de experiência unido a uma pesquisa
bibliográfica
Combinatorial high throughput synthesis of high entropy alloys
This PhD thesis is a part of the Accelerated Metallurgy (AccMet) project funded under the Seventh Framework Programme. AccMet’s aims consists on the delivery of an integrated pilot-scale facility for the combinatorial synthesis and testing of those unexplored material.
The contribution of this thesis to AccMet has been expanded in 3 years while focused in the understanding and development of a methodology suitable for the combinatorial synthesis of novel materials, and particularly of High Entropy Alloys (HEAs). These novel materials are composed of multiple elements at near equiatomic levels with the capacity of forming simple
crystalline phases such as bcc and fcc instead of the expected intermetallic compounds as well as their excellent combination of structural and functional properties compared to the traditional materials.
A mathematical technique known as Principal Component Analysis has been used here to identify patterns within a set of metallic systems forming a wide range of crystalline structures. This technique would not only speed up the compositional design stage but also contribute to the development of a virtual library containing all the explored systems.
Mercury Centre has been an important key during the synthesis of HEAs where Spark Plasma Sintering (SPS) and Electron Beam Melting (EBM) have been successfully applied for the development of the thesis.
The final combination of the design stage, production and characterisation of HEAs developed in this thesis would result in an advances technique suitable not only for the synthesis of novel HEAs, but also for the discovery of other unexplored systems
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