1,178 research outputs found

    Characteristic varieties of graph manifolds and quasi-projectivity of fundamental groups of algebraic links

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    The present paper studies the structure of characteristic varieties of fundamental groups of graph manifolds. As a consequence, a simple proof of Papadima's question is provided on the characterization of algebraic links that have quasi-projective fundamental groups. The type of quasi-projective obstructions used here are in the spirit of Papadima's original work.Comment: 22 pages, 6 figures, to appear in European Journal of Mathematic

    La libertad religiosa en el magisterio actual de la iglesia católica

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    A New Species of \u3ci\u3ePterygodermatites\u3c/i\u3e (Nematoda: Rictulariidae) from the Incan Shrew Opossum, \u3ci\u3eLestoros inca\u3c/i\u3e

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    Pterygodermatites (Paucipectines) hymanae n. sp. (Rictulariidae) collected from the Incan shrew opossum, Lestoros inca, from Peru is described herein. These nematodes show a subapical, slightly dorsal oral opening and a laterally compressed buccal capsule with 2 conspicuous lateral walls and a dorsal wall. Each lateroventral wall possesses 4 relatively large denticles, and the dorsal wall has 6 denticles. Females are characterized by a conspicuously large postvulvar 37th spine, which may reach 1 mm. This is the first record of endoparasites in the Incan shrew opossum and the fifth species of Pterygodermatites recorded in New World marsupials

    Properties of balanced flows with bottlenecks: Common stylized facts in finance and vibration-driven vehicles

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    We study experimentally the properties of the flow of mechanical vibration-driven vehicles confined in two chambers connected through a narrow opening. We report that the density of particles around the opening presents critical behavior and scaling properties. By mapping this density to the financial market price, we document that the main stylized facts observed in financial systems have their counterparts in the mechanical system. The experimental model accurately reproduces financial properties such as scaling of the price fluctuation, volatility clustering, and multiscaling.Fil: Patterson, Germán Agustín. Instituto Tecnológico de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sornette, D.. Universidad de Ginebra. Facultad de Ciencias. Sección de Física; SuizaFil: Parisi, Daniel Ricardo. Instituto Tecnológico de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Evaluación briológica de los efectos de la contaminación atmosférica en la Ciudad de México

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    The Index of Atmospheric Purity (IAP) was used to make a preliminary evaluation of epiphytic moss response to atmospheric pollution in the urban area of Mexico City. Areal analysis indicates that there is a significant negative correlation (p < 0.5) between IAP values and SO2, NO2, NOx, Pb and temperature values of -0.45, -0.90, -0.80, -0.80, -0.90. Significant positive correlation (p < 0.05) between IAP values and O3, rainfall and relative atmospheric humidity with values of 0.70, 0.80, 0.90. Increase in atmospheric pollutants in Mexico City have promoted a gradual decrease in frequency and cover of epiphytic mosses even though some ecological factors may show the oposite effect.Se hace una evaluación preliminar de la respuesta de los musgos epífitos a la contaminación atmosférica usando el Indice de Pureza Atmosférica (IPA) en el área urbana de la Ciudad de México. El análisis por zonas indica que hay una relación inversa y significativa (p < 0.5) entre el IPA y SO2, NO2, NOx, Pb y la temperatura con valores de -0.45, -0.90, -0.80, -0.80, -0.90. También se encontró una relación directa y significativa (p < 0.05) entre el IPA y el O3, la precipitación pluvial y la humedad relativa con valores de 0.70, 0.80, 0.90. Los incrementos en los niveles de algunos contaminantes atmosféricos en la Ciudad de México han promovido la disminución gradual en la frecuencia de aparición y cobertura de musgos epífitos, aunque algunas variables ambientales pueden tener el efecto opuesto

    Temporal variation of the total nitrogen concentration in aereal organs of nitrogen fixing and non fixing riparian species

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    Changes in nitrogen concentration was determinated in samples of Alnus glutinosa, Elaeagnus angustifolia, Populus x canadiensis and Ailanthus altissima leaves, petioles and branches periodically during a year. Maximum nitrogen percentage was found in diazotrophic species (Alnus and Elaeagnus) and the nitrogen retranslocation form branches was higher (2.5 times) in no fixing species.Se estudian 10s cambios en la concentración de nitrógeno en Alnus glutinosa, Elaeagnus angustifolia, Populus x canadiensis y Ailanthus altissima, en hojas, peciolos y tallos periódicamente durante un año. El porcentaje máximo de nitrógeno se encuentra en las especies diazotrofas (Alnus y Elaeagnus) y la retraslocación de dicho elemento desde los tallos es superior (2.5) veces) en las plantas no actinonizas

    Habitat use by armadillos in agroecosystems of central Argentina: does plot identity matter?

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    In agroecosystems, the use of cultivated plots by mammals depends on habitat structure as well as on the degree of species specialization. In the Pampas of Argentina, during the last 2-3 decades, there has been a continuing expansion of cropland. The aim of this study was to analyze how the identity and characteristics of agricultural plots may have affected the activity of 2 species of armadillos (Chaetophractus villosus and Dasypus hybridus) in a rural landscape. We carried out 4 sampling sessions between December 2011 and June 2013, surveying 175 plots during spring-summer and 194 during fall at 25 different sites in the Pampas of Buenos Aires province, Argentina. In each plot, we surveyed for signs (burrows and holes) along a 600×6 m transect in order to assess armadillo activity and measured 4 habitat structural variables. As expected, there were structural differences between types of agricultural plots. Across all plots, a total of 6,654 armadillo signs were found (C. villosus = 5,009, D. hybridus = 1,645). Generalized linear mixed models revealed that during both seasons, the type of plot explained much of the variation in armadillo activity, except during spring-summer for D. hybridus. C. villosus had higher use of plots with a longer history of non-tillage (e.g., soybean), while there was more evidence of D. hybridus activity in plots with less human intervention (e.g., grasslands), especially during fall. Overall, D. hybridus and C. villosus were more sensitive to the particular structural features of plots rather than to the kind of land use practiced (crop field or rangeland). These results have important implications for future management decisions in the Pampas region because during the last decades, farming of soybeans has expanded at the expense of grasslands, and this change appears to have differentially affected these 2 species of armadillos.Centro de Estudios Parasitológicos y de VectoresFacultad de Ciencias Naturales y Muse

    Atypical modulations of N170 component during emotional processing and their links to social behaviors in ex-combatants

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    ABSTRACT: Emotional processing (EP) is crucial for the elaboration and implementation of adaptive social strategies. EP is also necessary for the expression of social cognition and behavior (SCB) patterns. It is well-known that war contexts induce socio-emotional atypical functioning, in particular for those who participate in combats. Thus, ex-combatants represent an ideal non-clinical population to explore EP modulation and to evaluate its relation with SCB. The aim of this study was to explore EP and its relation with SCB dimensions such as empathy, theory of mind and social skills in a sample of 50 subjects, of which 30 were ex-combatants from illegally armed groups in Colombia, and 20 controls without combat experience. We adapted an Emotional Recognition Task for faces and words and synchronized it with electroencephalographic recording. Ex-combatants presented with higher assertion skills and showed more pronounced brain responses to faces than Controls. They did not show the bias toward anger observed in control participants whereby the latter group was more likely to misclassify neutral faces as angry. However, ex-combatants showed an atypical word valence processing. That is, words with different emotions yielded no differences in N170 modulations. SCB variables were successfully predicted by neurocognitive variables. Our results suggest that in ex-combatants the links between EP and SCB functions are reorganized. This may reflect neurocognitive modulations associated to chronic exposure to war experiences

    A study of the diffusion pattern in N=4 SYM at high energies

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    In the context of evolution nequations and scattering amplitudes in the high energy limit of the N=4 super Yang–Mills theory we investigate in some detail the BFKL gluon Green function at next-to-leading order. In particular, we study its collinear be havi or in term so fan expansion in different angular components. We also perform a Monte Carlo simulation of the different final states contributing to such a Green function and construct the diffusion pattern in to in frared and ultraviolet modes and multiplicity distributions, making emphasis in separating the gluon contributions from those of scalars and gluinos. We find that the combined role of the non-gluonic degree sof freedom is to improve the collinear behavior and reduce the diffusion in to ultraviolet regions while not having any effect ont heaver age multiplicities or diffusion in to the in frared. In terms of growth with energy,the non-zero conformal spin components are mainly driven by the gluon terms in the BFKLkernel. Forze rocon formal spin (Pomeron) the effect the scalar and gluino sectors is to dramatically push the Green function towards higher valuesF.C. thanks the Instituto de Física Teórica UAM/CSIC for the warm hospitality.Weack now ledge partial support from the European Comission under contract LHC PhenoNet (PITN-GA-2010-264564), the Comunidad de Madrid through HEPHACOSS2009/ESP-1473, and MICINN (FPA2010-17747) and Spanish MINECOs Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-0249.TheworkofF.C.was supported by EuropeanCommission, European Social Fund and Calabria Region,that disclaim many lia-bility for the use that can be done of the information provided in this Letter.G.C. thanks the support from the Research Executive Agency(REA)of the European Union under the Grant Agree ment number PIEF-GA-2011-298582 and by MICINN (FPA2011-23778,FPA2007-60323 and CSD2007-00042CPAN

    Reacciones de ciclización reductiva para la síntesis de nuevas benzodiazepinonas y benzotiadiazepinas S,S-dióxido

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    En este trabajo se describe la síntesis y ciclización de N-(2-nitrobencil)-2-cloroacetamidas así como de N-(2-aminobencil)-1-bromometansulfonamidas. La anelación de las amidas se produjo por ciclización reductiva con Fe proporcionando 1,2,4,5-tetrahidro-1,4-benzodiazepin-3-onas con muy buenos rendimientos. Para el caso de las N-(2-aminobencil)-1-bromometansulfonamidas, éstas fueron sometidas a ciclización intramolecular en distintos solventes (DMF, sulfolano) a distintas temperaturas no pudiéndose obtener el producto ciclado (3,1,4-benzotiadiazepinas 3,3-dióxido). En su defecto se obtuvo el producto de la reducción del grupo bromometansulfonilo a metansulfonilo con rendimientos aceptables. Todos los productos formados fueron caracterizados por espectroscopia 1H-RMN y 13C-RMN mono y bidimensional
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