149 research outputs found

    Thin-shell gravastar in a noncommutative BTZ geometry

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    In this paper, we build a thin-shell gravastar model within a noncommutative BTZ geometry. For this, we consider a noncommutative BTZ metric in the inner region and a geometry associated with a BTZ solution in the outer region, joined by the generalized join technique. After investigating the inner spacetime, surface and outer spacetime, we observe that there is a surface energy density and surface pressure, such as to make gravastar stable. This effect persists even when the cosmological constant is zero. Besides, we found a bound for the noncommutativity parameter. In addition, we examine the thermodynamics of the noncommutative BTZ black hole in Schwarzschildtype form in three-dimensional spacetime. We also check the stability condition by calculating the specific heat capacity.Comment: 12, 6 figure

    Pot culture of Iris xiphium (Holland Iris) with different concentrations of earthworm humus and their lixiviates

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    Se evaluaron tres variedades de Iris xiphium L. cultivadas en maceta en cuatro proporciones de humus de lombriz y se aplicaron los lixiviados diluidos como bioabono foliar. El experimento se realizó en un diseño completamente al azar con arreglo trifactorial y se midieron ocho variables: longitud de tallo (LT), longitud de botón (LB), longitud de flor (LF), diámetro de botón (DB), diámetro de flor (DF), biomasa (B), área foliar (AF) y días de cosecha (DDC). Los resultados indicaron que la variedad Telstar resultó ser la más precoz. El mejor tratamiento en dicha variedad para las variables LT, LB, B, DF y DDC correspondió a la proporción 30/70 (% lombrihumus / % suelo) y la dilución 1:10 de lixiviado; el segundo mejor tratamiento fue en la variedad Discovery en la proporción 40/60 (%lombrihumus / %suelo) y dilución 1:10 de lixiviado para las variables LT, AF y B. El presente trabajo aporta nueva información en cuanto al uso de sustratos y abono foliar orgánicos para el manejo sustentable, con bajo impacto ambiental, en cultivos florícolas.Growth in pots of three varieties of Iris xiphium was evaluated in four proportions of earthworm humus and diluted lixiviate used as foliar organic fertilizer. The experiment was conducted in a completely randomized three factorial design where the following variables were measured: stem length (SL), bud length (BL), flower (FL), bud diameter (BD), flower diameter (FD), biomass (B), leaf area (LA) and days to harvest (HD). The results showed that the 'Telstar' range turned out to be the earlier. The best treatment in the range 'Telstar' for variables SL, BL, B, FD and HD corresponded to the proportion 30% of earthworm along with the 1:10 dilution of lixiviate the second best treatment was in the Discovery range with 40% of earthworm and 1:10 dilution of lixiviate for variables LT, AF and B. In regards the proportions of used earthworm the best results were obtained in the proportions 30 and 40% with the use of the 1:10 dilution lixiviate. The present study provides new information on the use of organic substrates and foliar fertilizer for sustainable, low environmental impact, flower crops.Fil: Milpa-Mejía, Silvia. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Grenón-Cascales, Graciela N.. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: González-Castellanos, Anacleto. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Vázquez-García, Luis Miguel. Universidad Autónoma del Estado de México. Facultad de Ciencias Agrícola

    Cultivo en maceta de Iris xiphium L. (Iris de Holanda) con diferentes concentraciones de humus de lombriz y sus lixiviados

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    Se evaluaron tres variedades de Iris xiphium L. cultivadas en maceta en cuatro proporciones de humus de lombriz y se aplicaron los lixiviados diluidos como bioabono foliar. El experimento se realizó en un diseño completamente al azar con arreglo trifactorial y se midieron ocho variables: longitud de tallo (LT), longitud de botón (LB), longitud de flor (LF), diámetro de botón (DB), diámetro de flor (DF), biomasa (B), área foliar (AF) y días de cosecha (DDC). Los resultados indicaron que la variedad Telstar resultó ser la más precoz. El mejor tratamiento en dicha variedad para las variables LT, LB, B, DF y DDC correspondió a la proporción 30/70 (% lombrihumus / % suelo) y la dilución 1:10 de lixiviado; el segundo mejor tratamiento fue en la variedad Discovery en la proporción 40/60 (%lombrihumus / %suelo) y dilución 1:10 de lixiviado para las variables LT, AF y B. El presente trabajo aporta nueva información en cuanto al uso de sustratos y abono foliar orgánicos para el manejo sustentable, con bajo impacto ambiental, en cultivos florícolas.Se evaluaron tres variedades de Iris xiphium L. cultivadas en maceta en cuatro proporciones de humus de lombriz y se aplicaron los lixiviados diluidos como bioabono foliar. El experimento se realizó en un diseño completamente al azar con arreglo trifactorial y se midieron ocho variables: longitud de tallo (LT), longitud de botón (LB), longitud de flor (LF), diámetro de botón (DB), diámetro de flor (DF), biomasa (B), área foliar (AF) y días de cosecha (DDC). Los resultados indicaron que la variedad Telstar resultó ser la más precoz. El mejor tratamiento en dicha variedad para las variables LT, LB, B, DF y DDC correspondió a la proporción 30/70 (% lombrihumus / % suelo) y la dilución 1:10 de lixiviado; el segundo mejor tratamiento fue en la variedad Discovery en la proporción 40/60 (%lombrihumus / %suelo) y dilución 1:10 de lixiviado para las variables LT, AF y B. El presente trabajo aporta nueva información en cuanto al uso de sustratos y abono foliar orgánicos para el manejo sustentable, con bajo impacto ambiental, en cultivos florícolas

    La Práctica Veterinaria con Caninos Domésticos como Factor de Riesgo para la Exposición a Toxocara Canis en Lima, Perú

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    The frequency of seropositives and risk of exposure to Toxocara canis in the personnel working in veterinary clinics in the city of Lima was determined. An exposed group with direct contact to dogs (n=135) and a non-exposed group of administrative staff (n=108) were evaluated. Sera samples were analyzed by ELISA test using excretion/ secretion antigens of L2 larvi of T. canis in dilutions of 1/200, 1/400, 1/800, 1/1600 and greater than 1/1600, searching for IgG antibodies. In the exposed group, 95.6, 58.5, 37.0, 23.7 y 9.6% resulted positive in the dilutions studied, respectively, and in the non-exposed group 97.2, 50.0, 32.4, 17.6 y 3.7% resulted positive respectively. No association was found between the proportion of positives and the two groups. It was concluded that the professional practice does not represent a risk factor for the occurrence of human infections by T. canis.Se determinó la frecuencia de serorreactores y riesgo de exposición a Toxocara canis en el personal que laboraba en clínicas y consultorios veterinarios de la ciudad de Lima. Se consideró un grupo expuesto, en contacto directo con canes (n=135) y un grupo no expuesto, de personal administrativo (n=108). Los sueros fueron evaluados mediante una prueba de ELISA con antígenos de excreción / secreción de larvas L2 de T. canis, en diluciones de 1/200, 1/400, 1/800, 1/1600 y más de 1/1600, en búsqueda de anticuerpos IgG. En el grupo expuesto, el 95.6, 58.5, 37.0, 23.7 y 9.6% resultaron positivos en las diluciones indicadas, respectivamente, en tanto que en el grupo no expuesto se encontró el 97.2, 50.0, 32.4, 17.6 y 3.7%, respectivamente. No se encontró asociación entre la proporción de positivos y los grupos de exposición. Se concluye que la práctica profesional no representa un factor de riesgo para la presentación de infecciones humanas a T. cani

    Dual equivalence in models with higher-order derivatives

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    We introduce a class of higher-order derivative models in (2,1) space-time dimensions. The models are described by a vector field, and contain a Proca-like mass term which prevents gauge invariance. We use the gauge embedding procedure to generate another class of higher-order derivative models, gauge-invariant and dual to the former class. We show that the results are valid in arbitrary (d,1) space-time dimensions when one discards the Chern-Simons and Chern-Simons-like terms. We also investigate duality at the quantum level, and we show that it is preserved in the quantum scenario. Other results include investigations concerning the gauge embedding approach when the vector field couples with fermionic matter, and when one adds nonlinearity.Comment: RevTex4, 14 pages; new version includes duality at the quantum level, and new references. To be published in J. Phys.

    Constraints from orbital motions around the Earth of the environmental fifth-force hypothesis for the OPERA superluminal neutrino phenomenology

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    It has been recently suggested by Dvali and Vikman that the superluminal neutrino phenomenology of the OPERA experiment may be due to an environmental feature of the Earth, naturally yielding a long-range fifth force of gravitational origin whose coupling with the neutrino is set by the scale M_*, in units of reduced Planck mass. Its characteristic length lambda should not be smaller than one Earth's radius R_e, while its upper bound is expected to be slightly smaller than the Earth-Moon distance (60 R_e). We analytically work out some orbital effects of a Yukawa-type fifth force for a test particle moving in the modified field of a central body. Our results are quite general since they are not restricted to any particular size of lambda; moreover, they are valid for an arbitrary orbital configuration of the particle, i.e. for any value of its eccentricity ee. We find that the dimensionless strength coupling parameter alpha is constrained to |alpha| <= 1 10^-10-4 10^-9 for 1 R_e <= lambda <= 10 R_e by the laser data of the Earth's artificial satellite LAGEOS II, corresponding to M_* >= 4 10^9 -1.6 10^10. The Moon perigee allows to obtain |alpha| <= 3 10^-11 for the Earth-Moon pair in the range 15 R_e <= lambda = 3 10^10 - 4.5 10^10. Our results are neither necessarily limited to the superluminal OPERA scenario nor to the Dvali-Vikman model, in which it is M_* = 10^-6 at lambda = 1 R_e, in contrast with our bounds: they generally extend to any theoretical scenario implying a fifth-force of Yukawa-type.Comment: LaTex2e, 18 pages, 4 figures, 1 table, 81 reference

    Balancing the double‐edged sword effect of increased resistant starch content and its impact on rice texture: its genetics and molecular physiological mechanisms

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    Resistant starch (RS) is the portion of starch that escapes gastrointestinal digestion and acts as a substrate for fermentation of probiotic bacteria in the gut. Aside from enhancing gut health, RS contributes to a lower glycemic index. A genome‐wide association study coupled with targeted gene association studies was conducted utilizing a diverse panel of 281 resequenced Indica rice lines comprising of ~2.2 million single nucleotide polymorphisms. Low‐to‐intermediate RS phenotypic variations were identified in the rice diversity panel, resulting in novel associations of RS to several genes associated with amylopectin biosynthesis and degradation. Selected rice lines encoding superior alleles of SSIIa with medium RS and inferior alleles with low RS groups were subjected to detailed transcriptomic, metabolomic, non‐starch dietary fibre (DF), starch structural and textural attributes. The gene regulatory networks highlighted the importance of a protein phosphatase alongside multiple genes of starch metabolism. Metabolomics analyses resulted in the identification of several metabolite hubs (carboxylic acid, sugars and polyamines) in the medium RS group. Among DF, mannose and galactose from the water‐insoluble fraction were found to be highly associated with low and medium RS lines, respectively. Starch structural analyses revealed that a moderate increase in RS is also linked to an elevation of amylose 1 and amylose 2 fractions. Although rice lines with medium RS content negatively affected textural and viscosity properties in comparison to low RS, the textural property of medium RS lines was in the same acceptable range as IR64, a rice mega variety popular in Asia
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