12,879 research outputs found

    Induction of interleukin-1 alpha production by Porphyromonas gingivalis in mononuclear blood cell cultures from periodontitis patients

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    The capacity of mononuclear blood cells to produce interleukin-1 alpha (IL-1 alpha) after stimulation with Porphyromonas gingivalis in cell culture was studied. The results obtained with cells from periodontitis patients were compared with those from a control population. The concentration of IL-1 alpha in serum and saliva was also determined and compared with the concentration in mononuclear blood cell cultures. No significant relationship was found between the incidence of periodontitis or severity of the lesions and IL-1 alpha production in the presence of P. gingivalis. Nevertheless, 11 of 30 periodontitis patients, showed levels >30pg/ml of IL-1 alpha in mononuclear blood cell cultures stimulated by P. gingivalis, whereas only three healthy control showed these titers of IL-1 alpha.Nous avons étudiés la production d’interleukine-1 alpha (Il-1 alpha) par des monocytes sanguins en culture après stimulation par Porphyromonas gingivalis. Les résultats observés chez des patients atteints de parodontose ont été comparés avec ceux obtenus chez des témoins. La concentration de Il-1 alpha dans le sérum et la salive a également été comparée avec celle des cultures de monocytes. Nous n’avons pas trouvé de différences significatives entre la sévérité des lésions parodontales et les concentrations d’Il-1 alpha. Cependant, 11 des 30 patients atteints de parodontose présentaient des niveaux d’Il-1 alpha supérieurs à 30 µg/ml, tandis que seulement 3 témoins avaient des niveaux élevés

    A laser-scanning confocal microscopy study of carrageenan in red algae from seaweed farms near the Caribbean entrance of the Panama Canal

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    Kappaphycus alvarezii (Doty) Doty ex P.C. Silva, a red macroalga, is a commercial source of carrageenan, a widely used polysaccharide compound important in the food and pharmaceutical industries, in nanotechnology, and in pharmacological applications. Carrageenan is found mainly in the cell wall and in the intercellular matrix. This is the first study to propose the characterization of carrageenans in vitro, using the auto-fluorescence properties of the alga treated with different polyamines: putrescine, spermidine, and spermine. This study suggests a four-phase cultivation sequence for seaweed farmers to enhance and assess the potential carrageenan yield of their crops. In phase 1, seedlings were treated with each of the polyamines. Explants were subsequently transferred through two additional culture phases before being planted on the sea farms in phase 4 and then harvested after 60 days for analysis. Images from transverse sections of 11 representative cultured K. alvarezii samples were obtained at 561 nm excitation wavelength for both the cell center and the cell wall of each sample. Spectral data were also analyzed using the spectral phasor algorithm of SimFCS developed at the Laboratory for Fluorescence Dynamics (www.lfd.uci.edu). We report on the identification of several spectral fluorescence emission fingerprints from different auto-fluorescence compounds spatially mapped using this technique. These fingerprints have the potential to improve strain selection of explants for enhanced carrageenan yield in seaweed farming operations as well as to enable wholesale pricing to correspond with crop quality

    Field trials of an improved cost-effective device for detecting peridomestic populations of Triatoma infestans (Hemiptera: Reduviidae) in rural Argentina

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    An improved device for detecting peridomestic Triatoma infestans consisting of one-liter recycled Tetra Brik milk boxes with a central structure was tested using a matched-pair study design in two rural areas in Argentina. In Olta (La Rioja), the boxes were installed beneath the thatched roofs and on the vertical wooden posts of each peridomestic structure. After a 5-month exposure, at least one of the recovered boxes detected 88% of the 24 T. infestans-positive sites, and 86% of the 7 negative sites by timed manual collections at baseline. In Amamá (Santiago del Estero), the boxes were paired with the best performing prototype tested before (shelter unit). After 3 months, some evidence of infestation was detected in 89% (boxes) and 79% (shelters) of 18-19 sites positive by timed collections, whereas 19% and 16% of 32 negative sites were positive, respectively. Neither device differed significantly in the qualitative or quantitative collection of every sign of infestation. The installation site did not modify significantly the boxes' sampling efficiency in both study areas. As the total cost of each box was half as expensive as each shelter unit, the boxes are thus the most cost-effective and easy-to-use tool for detecting peridomestic T. infestans currently available.Fil: Vazquez Prokopec, Gonzalo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Ceballos, Leonardo A.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Salomón, Oscar Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Centro Nacional de Diagnóstico e Investigaciones Endemo-epidémicas; ArgentinaFil: Gurtler, Ricardo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentin

    Alterated Identities in Brazil: From the Samba Culture to the Sertanejo Culture

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    Cultural references regarding Brazilianness have generally been associated with samba, carnival, colors, and an aesthetic compendium typical of a pre-modernity recreated in cities like Rio de Janeiro or Salvador. A foreign observer would like to see in these lands references that would transport him to Antônio Carlos Jobim’s “The Girl from Ipanema” song or to identity traits that would indicate a ‘tropical Brazil’ related to people dancing in the rhythm of samba and bossa nova, and Copacabana beach. However, many socio-cultural changes progressively impacted the consumption of musical and aesthetic styles among Brazilians. Changes concerning musical styles’ preferences led to significant cultural changes that would modify the notion of Brazilianness imaginary in the first decades of the 21st century. The present paper addresses this eventual cultural and aesthetic references change, showing with decisive force what has been called ‘sertanejo culture’ in Brazil. Keywords: Brazilian culture; Cultural identity; Samba culture; Sertanejo culture; Musical styles. DOI: 10.7176/RHSS/12-18-04 Publication date:September 30th 202

    Symmetry, winding number and topological charge of vortex solitons in discrete-symmetry media

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    We determine the functional behavior near the discrete rotational symmetry axis of discrete vortices of the nonlinear Schr\"odinger equation. We show that these solutions present a central phase singularity whose charge is restricted by symmetry arguments. Consequently, we demonstrate that the existence of high-charged discrete vortices is related to the presence of other off-axis phase singularities, whose positions and charges are also restricted by symmetry arguments. To illustrate our theoretical results, we offer two numerical examples of high-charged discrete vortices in photonic crystal fibers showing hexagonal discrete rotational invariance.Comment: 6 pages, 2 figure

    Vertical mixing and coherent anticyclones in the ocean: the role of stratification

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    The role played by wind-forced anticyclones in the vertical transport and mixing at the ocean mesoscale is investigated with a primitive-equation numerical model in an idealized configuration. The focus of this work is to determine how the stratification impacts such transport. <br><br> The flows, forced only at the surface by an idealized wind forcing, are predominantly horizontal and, on average, quasigeostrophic. Inside vortex cores and intense filaments, however, the dynamics is strongly ageostrophic. <br><br> Mesoscale anticyclones appear as "islands" of increased penetration of wind energy into the ocean interior and they represent the maxima of available potential energy. The amount of available potential energy is directly correlated with the degree of stratification. <br><br> The wind energy injected at the surface is transferred at depth through the generation and subsequent straining effect of Vortex Rossby Waves (VRWs), and through near-inertial internal oscillations trapped inside anticyclonic vortices. Both these mechanisms are affected by stratification. Stronger transfer but larger confinement close to the surface is found when the stratification is stronger. For weaker stratification, vertical mixing close to the surface is less intense but below about 150 m attains substantially higher values due to an increased contribution of both VRWs, whose time scale is on the order of few days, and of near-inertial motions, with a time scale of few hours

    El efecto de la escala sobre los procesos de escorrentía superficial

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    [Resumen] En una pequeña cuenca bajo explotación de dehesa se investiga la generación de escorrentía superficial a distintas escalas. Ello incluye experimentos con lluvia simulada en microparcelas, mediciones del flujo superficial en eventos en 17 parcelas abiertas y una parcela. cerrada, y la producción de caudal de la cuenca y una subcuenca. Los coeficientes de escorrentía de las escalas consideradas se agrupan en dos conjuntos: valores bajos para la cuenca y subcuenca, y valores altos a escala de pedón y ladera. Los resultados demuestran que gran parte de la escorrentía producida en las vertientes se infiltra después en las zonas coluviales y fondos de valle. Además indican la importancia de estudiar varias escalas para entender los procesos hidrológicos que operan en cuencas.[Abstract] In a small catchment under the so-called dehesa landuse system, the production of surface runoff is investigated at different scales. This includes experiments with simulated rainfal1 at micro-plots, event-based measurements of overland flow at 17 open plots and 1 closed plot, and discharge production of the catchment and subcatchment. The runoff coefficients of the considered scales form two groups, with low values for the catchment and sub-catchment and high values for the microplots and hillslope plots. The results show that large part of runoff produced at the slopes is infiltrated afterwards at colluvial sites and the valley floors.Furthemore, they indicate the importance of studying at various scales in order to understand the hydrological processes operating in catchment
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