266 research outputs found

    Compression methods for XUV attosecond pulses

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    none5noneMark Mero;Fabio Frassetto;Paolo Villoresi;Luca Poletto;Katalin VarjúMark, Mero; Fabio, Frassetto; Villoresi, Paolo; Luca, Poletto; Katalin, Varj

    The steric influence of extra-framework cations on framework flexibility:An LTA case study

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    The theoretical extent of framework flexibility of Zeolite A (LTA) in response to the steric and geometric effects of different Si/Al compositions and extra-framework cation content has been explored using GASP software. Flexibility windows and compression mechanisms for siliceous LTA and aluminosilicate Na-LTA, Ca-LTA and K-LTA have been modelled. As expected, relatively small cations in the zeolite pores have little effect on the range of flexibility observed. Aluminosilicate LTA, Na-LTA and Ca-LTA frameworks exhibit identical flexibility windows and these frameworks also follow the same compression mechanisms. The introduction of larger K+ ions, however, results in greater steric hindrance. This restricts the flexibility of the framework and alters the compression mechanism to accommodate these larger cations. It is shown that the limits of the flexibility window of Zeolite A are dependent on framework aluminium content and extra-framework cation size.</p

    Diagnosis of Linking Activities of the Faculty of Agricultural Engineering of Universidad Tecnica De Manabi

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    The aim of the study is to determine the contribution of universities to the development of society through linkage projects carried out by students of the Faculty of Agricultural Engineering at the Universidad Técnica de Manabí. At work, the results achieved in the institutional evaluation and self-assessment racing related indicators linking with society and offered projects are identified by the career of Agricultural Engineering in the period of the past five years are analyzed. Later a survey was applied to communities to determine their needs are the same, in order to compare the offered with the defendant and propose improvements in the process. The results of the survey of the communities show that some of the defendant's themes have not been offered so not being met community needs. As a result of this diagnosis strategy that support the continuous improvement of the process of linking with society career of Agricultural Engineering, Universidad Técnica de Manabí and contribute to social and economic development of the territory they are proposed

    Genetic regulation of glucoraphanin accumulation in Beneforté® broccoli

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    Diets rich in broccoli (Brassica oleracea var italica) have been associated with maintenance of cardiovascular health and reduction in risk of cancer. These health benefits have been attributed to glucoraphanin that specifically accumulates in broccoli. The development of broccoli with enhanced concentrations of glucoraphanin may deliver greater health benefits. Three high-glucoraphanin F1 broccoli hybrids were developed in independent programmes through genome introgression from the wild species Brassica villosa. Glucoraphanin and other metabolites were quantified in experimental field trials. Global SNP analyses quantified the differential extent of B. villosa introgression The high-glucoraphanin broccoli hybrids contained 2.5–3 times the glucoraphanin content of standard hybrids due to enhanced sulphate assimilation and modifications in sulphur partitioning between sulphur-containing metabolites. All of the high-glucoraphanin hybrids possessed an introgressed B. villosa segment which contained a B. villosa Myb28 allele. Myb28 expression was increased in all of the high-glucoraphanin hybrids. Two high-glucoraphanin hybrids have been commercialised as Beneforte broccoli. The study illustrates the translation of research on glucosinolate genetics from Arabidopsis to broccoli, the use of wild Brassica species to develop cultivars with potential consumer benefits, and the development of cultivars with contrasting concentrations of glucoraphanin for use in blinded human intervention studie

    Landau damping in thin films irradiated by a strong laser field

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    The rate of linear collisionless damping (Landau damping) in a classical electron gas confined to a heated ionized thin film is calculated. The general expression for the imaginary part of the dielectric tensor in terms of the parameters of the single-particle self-consistent electron potential is obtained. For the case of a deep rectangular well, it is explicitly calculated as a function of the electron temperature in the two limiting cases of specular and diffuse reflection of the electrons from the boundary of the self-consistent potential. For realistic experimental parameters, the contribution of Landau damping to the heating of the electron subsystem is estimated. It is shown that for films with a thickness below about 100 nm and for moderate laser intensities it may be comparable with or even dominate over electron-ion collisions and inner ionization.Comment: 15 pages, 2 figure

    Choice of sprint start performance measure affects the performance-based ranking within a group of sprinters: which is the most appropriate measure?

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    Sprint start performance has previously been quantified using several different measures. This study aimed to identify whether different measures could influence the performance-based ranking within a group of 12 sprinters, and if so, to identify the most appropriate measure. None of the 10 performance measures ranked all sprinters in the same order; Spearman's rho correlations between different block phase measures ranged from 0.50 to 0.94, and between block phase measures and those obtained beyond block exit from 0.66 to 0.85. Based on the consideration of what each measure quantifies, normalised average horizontal external power was identified as the most appropriate, incorporating both block velocity and the time spent producing this velocity. The accuracy with which these data could be obtained in an externally valid field setting was assessed against force platform criterion data. For an athlete producing 678 ± 40 W of block power, a carefully set-up manual high-speed video analysis protocol produced systematic and random errors of +5 W and ± 24 W, respectively. Since the choice of performance measure could affect the conclusions drawn from a technique analysis, for example the success of an intervention, it is proposed that external power is used to quantify start performance

    Geometric Model of a Coastal Aquifer to Promote the Sustainable Use of Water. Manglaralto, Ecuador

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    Modeling an aquifer provides significant advantages when evaluating and estimating the water resource for its sustainable use. This study focuses on the rural parish Manglaralto, a semi-arid area with a shortage of water, and without supply service by the public network. Still, it has a great demand for supply by the local and floating population (tourism). This has caused the coastal aquifer, which supplies the area’s water, to show signs of overexploitation, and its natural balance is compromised. The aim is to establish a geometric model of the aquifer through geological and geophysical analysis to set sustainable water-use guidelines. The methodology includes: (i) the processing of the current technical and hydrogeological information to know the aquifer’s data; (ii) geometric modeling of the aquifer through the correlation of technical information, using the GeoModeller software; (iii) proposals for the sustainable use of water in the framework of the United Nations’ Agenda 2030. The geometric model results reveal that the aquifer’s thickness varies from 4 m at the head of the river to 30 m at the sea’s mouth. The volume of water is estimated at 13.6 Hm3. The sustainable-use proposals ensure that more than half of the population receives the community company’s service. More than 40% of the territory is a protected area, and 64% of the population has sewerage service. This geometric model is a visual contribution that allows us to know the aquifer’s shape and establishes guidelines that help strengthen the water supply’s development and sustainability over time

    Strategies for the Development of the Value of the Mining-Industrial heritage of the Zaruma -Portovelo, Ecuador, in the Context of a Geopark Project

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    The enhancement of heritage resources helps to promote conservation, contributes to more significant and better protection, and favors the efficient use of these resources. Many heritage works and liabilities linked to mining activity are abandoned, causing the deterioration of heritage resources that may become environmental liabilities over time. This work aims to develop strategies for the development of the Mining-Industrial heritages through participatory methods for geomining enhancement and development of places in the Zaruma-Portovelo area. The proposed methodology consists of: (i) The creation and development of a database with several publications and documents that register the Mining-Industrial heritage sites; (ii) The assessment of mining-industrial sites based on criteria or methodologies proposed by other authors; (iii) Focal group work considering: (a) The identification and cataloging geosites of interest, (b) The creation and/or development of museums, tourist mines, mineral routes or geoparks in which the natural and geological-mining factors complement each other and (iv) SWOT analysis and matrix which provides several strategies for value-making of geomining heritage and its promotion in the development of geotourism in a project proposal for Zaruma and its surroundings. In conclusion, this work includes twelve unified mining sites in the Proposal for Geopark ‘Ruta del Oro,’ as a strategy to guarantee the conservation of heritage values and contribute to local development and geotourism

    Association of Genetic Markers with CSF Oligoclonal Bands in Multiple Sclerosis Patients

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    Objective:to explore the association between genetic markers and Oligoclonal Bands (OCB) in the Cerebro Spinal Fluid (CSF) of Italian Multiple Sclerosis patients.Methods:We genotyped 1115 Italian patients for HLA-DRB1*15 and HLA-A*02. In a subset of 925 patients we tested association with 52 non-HLA SNPs associated with MS susceptibility and we calculated a weighted Genetic Risk Score. Finally, we performed a Genome Wide Association Study (GWAS) with OCB status on a subset of 562 patients. The best associated SNPs of the Italian GWAS were replicated in silico in Scandinavian and Belgian populations, and meta-analyzed.Results:HLA-DRB1*15 is associated with OCB+: p = 0.03, Odds Ratio (OR) = 1.6, 95% Confidence Limits (CL) = 1.1-2.4. None of the 52 non-HLA MS susceptibility loci was associated with OCB, except one SNP (rs2546890) near IL12B gene (OR: 1.45; 1.09-1.92). The weighted Genetic Risk Score mean was significantly (p = 0.0008) higher in OCB+ (7.668) than in OCB- (7.412) patients. After meta-analysis on the three datasets (Italian, Scandinavian and Belgian) for the best associated signals resulted from the Italian GWAS, the strongest signal was a SNP (rs9320598) on chromosome 6q (p = 9.4×10-7) outside the HLA region (65 Mb).Discussion:genetic factors predispose to the development of OCB

    Dynamics of Macrophage Trogocytosis of Rituximab-Coated B Cells

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    Macrophages can remove antigen from the surface of antibody-coated cells by a process termed trogocytosis. Using live cell microscopy and flow cytometry, we investigated the dynamics of trogocytosis by RAW264.7 macrophages of Ramos B cells opsonized with the anti-CD20 monoclonal antibody rituximab. Spontaneous and reversible formation of uropods was observed on Ramos cells, and these showed a strong enrichment in rituximab binding. RAW-Ramos conjugate interfaces were highly enriched in rituximab, and transfer of rituximab to the RAW cells in submicron-sized puncta occurred shortly after cell contact. Membrane from the target cells was concomitantly transferred along with rituximab to a variable extent. We established a flow cytometry-based approach to follow the kinetics of transfer and internalization of rituximab. Disruption of actin polymerization nearly eliminated transfer, while blocking phosphatidylinositol 3-kinase activity only resulted in a delay in its acquisition. Inhibition of Src family kinase activity both slowed acquisition and reduced the extent of trogocytosis. The effects of inhibiting these kinases are likely due to their role in efficient formation of cell-cell conjugates. Selective pre-treatment of Ramos cells with phenylarsine oxide blocked uropod formation, reduced enrichment of rituximab at cell-cell interfaces, and reduced the efficiency of trogocytic transfer of rituximab. Our findings highlight that dynamic changes in target cell shape and surface distribution of antigen may significantly influence the progression and extent of trogocytosis. Understanding the mechanistic determinants of macrophage trogocytosis will be important for optimal design of antibody therapies
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