Variations in flowering phenology and reproductive success in Setaria lachnea
Exner, Eliana de Luján; Zabala, Juan Marcelo; Pensiero, Jose Francisco
Setaria lachnea, moha perenne, is a native grass with excellent forage quality; thus, its introduction to cultivation has been recommended. Therefore, in the present study, the variability in flowering phenology and reproductive success of three Argentine populations from different places by altitudinal gradient have been analyzed, with respect to points of interest for selecting materials. A completely randomized experimental design was used, with 10 genotypes per population and 3 replications per genotype. Flowering phenology was analyzed through variables of flowering start and mid-flowering; the number of panicles was quantified by observation, the number of the total of panicles and reproductive success by fruiting percentage. For flowering start only significant (p£0.05) intrapopulation variations were found. Seventy-five percent of the genotypes started flowering in November 2005. For mid-flowering, there were significant inter- and intra-population differences (p£0.05). The intrapopulation variability observed will allow selecting genotypes with prolonged vegetative period. Reproduction success, measured as mean fruiting percentage, was 41 (high for a nondomesticated species), with variation from 3 % to 80 %. In the two analyzed years (2005-2006), significant inter- and intra-population differences (p£0.05) were found. Genotypes of the population of less height stood out by their high fruiting percentage, always above 40 %; however, there was no variation pattern associated to altitude. Beginning of flowering was not correlated with fruiting percentage; therefore, it will be possible to select late-ripening materials, without altering fruiting percentage. , moha perenne, is a native grass with excellent forage quality; thus, its introduction to cultivation has been recommended. Therefore, in the present study, the variability in flowering phenology and reproductive success of three Argentine populations from different places by altitudinal gradient have been analyzed, with respect to points of interest for selecting materials. A completely randomized experimental design was used, with 10 genotypes per population and 3 replications per genotype. Flowering phenology was analyzed through variables of flowering start and mid-flowering; the number of panicles was quantified by observation, the number of the total of panicles and reproductive success by fruiting percentage. For flowering start only significant (p£0.05) intrapopulation variations were found. Seventy-five percent of the genotypes started flowering in November 2005. For mid-flowering, there were significant inter- and intra-population differences (p£0.05). The intrapopulation variability observed will allow selecting genotypes with prolonged vegetative period. Reproduction success, measured as mean fruiting percentage, was 41 (high for a nondomesticated species), with variation from 3 % to 80 %. In the two analyzed years (2005-2006), significant inter- and intra-population differences (p£0.05) were found. Genotypes of the population of less height stood out by their high fruiting percentage, always above 40 %; however, there was no variation pattern associated to altitude. Beginning of flowering was not correlated with fruiting percentage; therefore, it will be possible to select late-ripening materials, without altering fruiting percentage.
White rot fungi laccases for biotechnological applications
Villalba, Laura L.; Fonseca, Maria Isabel; Giorgio, Ernesto Martín; Zapata, Pedro Dario
White rot fungi have an enzymatic system producing oxidative and hydrolytic enzymes that act on the degradation of certain components of the cell wall. They can be applied in several technological processes, such as paper industry, bio-fuels and environmental pollution. Laccases are multi-copper enzymes of wide substrate specificity and high non-specific oxidation capacity that use molecular oxygen to oxidize various aromatic compounds, and are highly relevant biotechnological applications. In this review, we present some significant patents on laccase production and recombinant DNA technology for diverse biotechnology applications.
Composition of fractional Orlicz maximal operators and A1-weights on spaces of homogeneous type
Bernardis, Ana Lucia; Pradolini, Gladis Guadalupe; Lorente, María; Riveros, Maria Silvina
For a Young function Θ with 0 ≤ α < 1, let Mα,Θ be the fractional Orlicz maximal operator defined in the context of the spaces of homogeneous type (X, d, μ) by Mα,Θf(x) = supx∈Bμ(B)α{double pipe}f{double pipe}Θ,B, where {double pipe}f{double pipe}Θ,B is the mean Luxemburg norm of f on a ball B. When α = 0 we simply denote it by MΘ. In this paper we prove that if Φ and Ψ are two Young functions, there exists a third Young function Θ such that the composition Mα,Ψ {ring operator} MΦ is pointwise equivalent to Mα,Θ. As a consequence we prove that for some Young functions Θ, if Mα,Θf <∞ a.e. and δ ∈ (0,1) then (Mα,Θf)δ is an A1-weight.
Interaction of triflupromazine with distearoylphosphatidylglycerol films studied by surface pressure isotherms and cyclic voltammetry at a 1,2-dichloroethane/water interface
Colqui Quiroga, Mónica Vanesa; Monzon, Lorena Maria Aranzazu; Yudi, Lidia Mabel
The effect of triflupromazine (TFP) on molecular packing of distearoylphosphatidylglycerol (DSPG), adsorbed at the water/1,2-dichloroethane interface, was investigated using cyclic voltammetry (CV) and surface pressure-molecular area isotherm. TFP partition in the DSPG monolayer changes the structure of the film. The results indicate that a fluidizing effect, dependent on the time and the drug concentration, takes place leading to an increase in the permeability of the film. This effect is produced by TFP either from the organic or from the aqueous phase due to the amphiphilic nature of this drug. Nevertheless, the expansion of the film is enhanced when TFP acts from the aqueous phase
Respuestas inmunológicas de las plantas frente al ataque de insectos
Zavala, Jorge Alberto
Las plantas se defienden de sus consumidores a través de sofisticados mecanismos que incluyen pelos urticantes, espinas, compuestos tóxicos para los atacantes o bien compuestos atrayentes para sus depredadores. La comprensión de los procesos moleculares que subyacen en estas respuestas defensivas develan algunos de los misterios acerca de la íntima relación que une a plantas y herbívoros.
Acerca de la elaboración y publicación de la ley en el Derecho indiano
Tau Anzoategui, Víctor
El autor retoma y profundiza anteriores estudios dedicados al problema histórico de la ley en América española entre los siglos XVI y principios del XIX. Luego de establecer el significado de los vocablos que componen el título, el trabajo se ocupa del Consejo, deliberación, elaboración y motivación de las leyes, así como también de las formas de promulgación y publicación. En las consideraciones finales se destacan las peculiaridades de un orden elaborado con sentido creativo por generaciones de juristas para las Indias españolas con posible exposición a otros espacios territoriales y prolongación más allá de la extinción del poder español en América. Este artículo fue elaborado a invitación de la Dirección del Anuario para integrar la posición especial de un volumen monográfico dedicado al tema: "La publicación de las normas en la historia del Derecho español: la era de la imprenta".
Una ilustre familia: la reivindicación del autor en el ensayo de Mario Vargas Llosa
Perilli, Carmen Noemi
Los ensayos literarios de Mario Vargas Llosa disputan el espacio teórico y crítico latinoamericano. Proponen una poética novelesca y un canon literario. Se centran en el Autor y unen dos tradiciones: la narrativa romántica del vate y la narrativa moderna del experto. Vargas Llosa arma el catálogo de una vasta familia de escritores. Las formas vinculares propias de las filiaciones biológicas se apoderan de las afiliaciones culturales. La comunidad está constituida por varones neo-europeos, ilustrados y heterosexuales. Padres, hermanos e hijos marcan la distancia entre un nosotros y ellos/ellas. El nosotros está en el orden de la identidad, alejado de toda alteridad étnica, genérica o cultural. Las figuraciones de autor construyen el linaje del escritor y actúan como dobles especulares que autorizan su escritura.; Mario Vargas Llosa’s literary essays dispute the Latin American theoretical and critical space. They propose a poetic of the novel and a literary canon. Centering on the Author, they link two traditions: the romantic narrative of bards, and the modern narrative of experts. Vargas Llosa assembles a catalog of a vast family of writers. Biological filiation relations take over cultural affiliations. He enlists only heterosexual, illustrated and neo-european males. Fathers, brothers and sons mark the distance between “we” and male/female “they”. “We” is of the order of identity, excluding any ethnic, gender or cultural alterity. Author figurations construct the writer’s lineage, acting as specular doubles authorizing his writing.
On a partly linear autoregressive model with moving average errors
Bianco, Ana Maria; Boente Boente, Graciela Lina
In this paper, we generalise the partly linear autoregression model considered in the literature by including moving average errors when we want to allow a large dependence to the past observations. The strong ergodicity of the process is derived. A consistent procedure to estimate the parametric and nonparametric components is provided together with a test statistic that allows to check the presence of a moving average component in the model. Also, a Monte Carlo study is carried out to check the performance of the given proposals.
Stable p-branes in Chern-Simons AdS supergravities
Edelstein, Jose Daniel; Garbarz, Alan Nicolás; Mišković, Olivera; Zanelli, Jorge
We construct static codimension-two branes in any odd dimension D, with a negative cosmological constant, and show that they are exact solutions of Chern-Simons (super)gravity theory for (super)AdSD coupled to external sources. The stability of these solutions is analyzed by counting the number of preserved supersymmetries. It is shown that static massive (D 3)-branes are unstable unless some suitable gauge fields are added and the brane is extremal. In particular, in three dimensions, a 0-brane is recognized as the negative mass counterpart of the Ban˜ados-Teitelboim-Zanelli black hole. For these 0- branes, we write explicitly magnetically charged Bogomol’nyi-Prasad-Sommerfield states with various numbers of preserved supersymmetries within the OSpðp j 2Þ OSpðq j 2Þ supergroups. In five dimensions, we prove that stable 2-branes with magnetic charge always exist for the generic supergroup SUð2; 4 j NÞ, where N 4. For the special case N ¼ 4, in which Chern-Simons supergravity requires the addition of a nontrivial gauge field configuration in order to preserve the maximal number of degrees of freedom, we show for two different static 2-branes that they are Bogomol’nyi-Prasad-Sommerfield states (one of which is the ground state), and from the corresponding algebra of charges we show that the energy is bounded from below. In higher dimensions, our results admit a straightforward generalization, although there are presumably more solutions corresponding to different intersections of the elementary objects.
Joint diagnostic of the surface air temperature in southern South America and the Madden–Julian oscillation
Naumann, Gustavo; Vargas, Walter Mario
The objective of this research is to explore the relationship between maximum and minimum temperatures, daily precipitation, and the Madden–Julian oscillation (MJO). It was found that the different phases of the MJO show a consistent signal on winter temperature variability and precipitation in southeastern South America. Additionally, this paper explores the spatial–temporal variations of mutual information and joint entropy between temperature and the MJO. A defined spatial pattern was observed with an increased signal in northeastern Argentina and southern Brazil. In the local mutual information analysis, periods in which the mutual information doubled the average values were observed over the entire region. These results indicate that these connections can be used to forecast winter temperatures with a better skill score in situations where both variables covary.
On the formal semantics of IF-like logics
Figueira, Santiago; Gorin, Daniel Alejadro; Grimson, Rafael
In classical logics, the meaning of a formula is invariant with respect to the renaming of bound variables. This property, normally taken for granted, has been shown not to hold in the case of Independence Friendly (IF) logics. In this paper we argue that this is not an inherent characteristic of these logics but a defect in the way in which the compositional semantics given by Hodges for the regular fragment was generalized to arbitrary formulas. We fix this by proposing an alternative formalization, based on a variation of the classical notion of valuation. Basic metatheoretical results are proven. We present these results for Hodges’ slash logic (from which these can be easily transferred to other IF-like logics) and we also consider the flattening operator, for which we give novel game-theoretical semantics.
Optimization problem for extremals of the trace inequality in domains with holes
del Pezzo, Leandro Martin
We study the Sobolev trace constant for functions defined in a bounded domain Ω that vanish in the subset A. We find a formula for the first variation of the Sobolev trace with respect to the hole. As a consequence of this formula, we prove that when Ω is a centered ball, the symmetric hole is critical when we consider deformation that preserve volume but is not optimal for some case.
Normalization of Rings
Greuel, Gert Martin; Laplagne, Santiago Jorge; Seelisch, Frank
We present a new algorithm to compute the integral closure of a reduced Noetherian ring in its total ring of fractions. A modification, applicable in positive characteristic, where actually all computations are over the original ring, is also described. The new algorithm of this paper has been implemented in Singular, for localizations of affine rings with respect to arbitrary monomial orderings. Benchmark tests show that it is in general much faster than any other implementation of normalization algorithms known to us.
Bass' NK groups and cdh-fibrant Hochschild homology
Cortiñas, Guillermo Horacio; Haesemeyer, C.; Walker, Mark E.; Weibel, C.
The K-theory of a polynomial ring R[t] contains the K-theory of R as a summand. For R commutative and containing Q, we describe K∗(R[t])/K∗(R) in terms of Hochschild homology and the cohomology of Kähler differentials for the cdh topology. We use this to address Bass’ question, whether Kn(R) = Kn(R[t]) implies Kn(R) = Kn(R[t1,t2]). The answer to this question is affirmative when R is essentially of finite type over the complex numbers, but negative in general.
Análisis del control geológico en la torrencialidad del arroyo Las Lajas, Córdoba, a través de la modelización hidrológica; Analysis of the geological control on the Arroyo Las Lajas, Cordoba, flashiness through an hydrological modeling
Doffo, Nelso; Eric, Carlos F.; Gonzalez Bonorino, Gustavo
Se analiza la incidencia de factores litológicos, estructurales y bióticos en la respuesta hidrológica (torrencialidad) de una cuenca hídrica serrana aplicando el modelo matemático ARHymo. La cuenca alta del arroyo Las Lajas se encuentra en las sierras de Comechingones, entre 1.200 y 750 m s.n.m., con una superficie de 41 km2 y una red de drenaje de orden de Horton 6. La morfología de la cuenca está fuertemente controlada por la traza de la falla Las Lajas, una estructura de actividad reciente que separa un sustrato granítico de otro metamórfico. Para el modelado, la cuenca alta fue subdividida en 42 subcuencas. Para cada una de ellas se obtuvieron valores de curva número (CN). La torrencialidad de cada subcuenca fue estimada en base a los tiempos al pico (Tp) y a la distribución temporal de la onda de creciente reflejada en los hidrogramas. Se confrontaron las formas de los hidrogramas de subcuencas representativas y la distribución de las frecuencias de los tiempos al pico, con las características geológicas de la cuenca. Las subcuencas desarrolladas en metamorfitas con fuerte control estructural mostraron mayor torrencialidad que las ubicadas en el sustrato granítico.; The impact of lithological, structural and biotic factors in the hydrological response of a mountain drainage basin is analyzed using the mathematical model ARHymo. The upstream reach of the Las Lajas creek is located in the Comechingones Ranges, between 1,200 to 750 m a.s.l.; it has an area of 41 km2 and a drainage network of Horton order 6. The morphology of the basin is strongly controlled by the Las Lajas fault, a recently active structure that separates granitic from metamorphic substrates. The basin was subdivided into 42 subbasins and curve numbers were computed for each subbasin. The flashiness of the flood wave was estimated from time-to-peak data and from the shapes of hydrographs. Comparison of the shapes of the hydrographs of representative subbasins and the distribution of time-to-peak frequencies, with the geological features of the basin, suggests that the subbasins developed on metamorphic substrate show greater flashiness than those located on granitic substrate.
Social isolation and stress related hormones modulate the stimulating effect of ethanol in preweanling rats
Arias Grandio, Carlos; Solari, Ana Clara; Mlewski, Estela Cecilia; Miller, Stacie; Haymal, Olga Beatriz; Spear, Norman E.; Molina, Juan Carlos
Preweanling rats are highly sensitive to the locomotor stimulation induced by relatively high ethanol doses. In adult mice this ethanol effect is modulated by stress. The goal of the present study was to analyze the role of stress and corticosterone in the stimulating effect of ethanol in preweanling rats. In Experiment 1 15-day-old rats were separated from the mother during a period of 4 h in which subjects remained isolated or paired with a littermate. In a third condition pups remained in the home-cage with the dam. After this isolation period pups were given ethanol (0 or 2.5 g/kg) and were tested in a novel environment. Previous data have shown that a similar period of isolation is enough to increase corticosterone levels in preweanling rats. Experiment 2 evaluated the effect of exogenous administration of corticosterone (0, 3 or 6 mg/kg) along with ethanol, and Experiment 3 tested ethanol-mediated locomotor activation in adrenalectomized preweanling rats. The last experiment aimed to test the role of corticotropic releasing factor 1 (CRF1) receptors in locomotion induced by ethanol in isolated pups. According to our results there is a synergism between stress or corticosterone and ethanol in preweanling rats. The interaction between stress (induced by social isolation) and ethanol seems to be mediated by CRF, since blockade of CRF1 receptors cancelled the effect of ethanol in isolated pups. This study highlights the importance of considering stress as a possible intervening variable in studies evaluating ethanol effects in developing animals when maternal separation is used in the experimental procedure.
Vibrational spectra of magnesium oxalates
D'Antonio, Maria C.; Mancilla Haselbach, Nancy Beatriz; Wladimirsky, Alejandra; Palacios, Daniel; Gonzalez Baro, Ana Cecilia; Baran, Enrique José
The infrared and Raman spectra of anhydrous MgC2O4 as well as those of the two polymorphic forms of the dihydrated oxalate, α-MgC2O4·2H2O and β-MgC 2O4·2H2O, were recorded and discussed on the basis of their structural peculiarities and in comparison with the spectra of natural α-MgC2O4·2H2O (the mineral glushinskite). Some comparisons between these polymorphs and with other, previously investigated, oxalate complexes were made. The IR spectra of partially deuterated samples of α-MgC2O4· 2H2O were also discussed, reinforcing some of the performed assignments.
Calidad de agua para la producción de especies animales tradicionales y no tradicionales en Argentina; Water quality for the production of traditional and non traditional animal species in Argentina
Fernandez Cirelli, Alicia; Moscuzza, Carlos Hernán; Pérez Carrera, Alejo Leopoldo; Volpedo, Alejandra
La calidad de agua es un factor determinante de la producción de especies animales tradicionales y no tradicionales, debido a su relación con los requerimientos nutricionales de cada especie. Los criterios que habitualmente se consideran para la determinación de la calidad del agua de bebida son sus propiedades físicoquímicas y organolépticas, la presencia de compuestos tóxicos y de bacterias patógenas, y el exceso de minerales. En este trabajo se presenta una revisión de los estudios de calidad de agua para las producciones animales tradicionales (producción de carne y leche bovinas) y no tradicionales (acuicultura y pesca de captura) para diferentes regiones de Argentina con el objetivo de analizar las carencias de información y proponer la intensificación de estudios que permitan mejorar los sistemas de producción animal de nuestro país.; Water quality is a determining factor in the production of both traditional and nontraditional animal species since it is related to the nutritional requirements of each species. Water quality criteria often include physical- chemical and organoleptic properties, the presence of toxic compounds and pathogenic bacteria as well as mineral excess. The aim of this work is to review studies on water quality for the production of traditional (bovine meat and milk) and non-traditional animal species (aquaculture and capture fisheries) in different regions of Argentina. The identification of information gaps will be the basis for new studies to improve animal production systems in Argentina.