Free QQ-distributive lattice over an nn-element chain

In this note we provide an explicit construction of $FQ({\bf n})$, the free $Q$-distributive lattice over an $n$-element chain, different from those given by Cignoli [4] and Abad--Díaz Varela [1], and prove that $FQ({\bf n})$ can be endowed with a structure of a De Morgan algebra.Fil: Monteiro, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; ArgentinaFil: Abad, Manuel. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Zander, Marta Amalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Nacional del Sur. Departamento de Matemática; Argentin

Non-Abelian dark matter and dark radiation

We propose a new class of dark matter models with unusual phenomenology. What is ordinary about our models is that dark matter particles are WIMPs, they are weakly coupled to the Standard Model and have weak scale masses. What is unusual is that they come in multiplets of a new "dark" non-Abelian gauge group with milli-weak coupling. The massless dark gluons of this dark gauge group contribute to the energy density of the universe as a form of weakly self-interacting dark radiation. In this paper we explore the consequences of having i.) dark matter in multiplets ii.) self-interacting dark radiation and iii.) dark matter which is weakly coupled to dark radiation. We find that i.) dark matter cross sections are modified by multiplicity factors which have significant consequences for collider searches and indirect detection, ii.) dark gluons have thermal abundances which affect the CMB as dark radiation. Unlike additional massless neutrino species the dark gluons are interacting and have vanishing viscosity and iii.) the coupling of dark radiation to dark matter represents a new mechanism for damping the large scale structure power spectrum. A combination of additional radiation and slightly damped structure is interesting because it can remove tensions between global $\Lambda$CDM fits from the CMB and direct measurements of the Hubble expansion rate ($H_0$) and large scale structure ($\sigma_8$).Comment: 25 pages, 8 figures; v2: minor improvements, references added; v3: added references and an acknowledgement note to J. Lesgourgues; accepted for publication in PR

La cláusula de reserva de dominio en los contratos de venta de bienes muebles con precio aplazado

La masiva oferta y adquisición de bienes de consumo, fundamentalmente de bienes muebles, ha convertido en una constante la necesidad de encontrar aquellas garantías que permitan asegurar de un modo eficaz la satisfacción de sus créditos a los acreedores. Sin lugar a dudas, la reserva de dominio constituye hoy día una de esas garantías que, con una mayor eficacia, asegura a los vendedores y financiadores el cobro de sus créditos nacidos en el ámbito o sector mobiliario. La reserva de dominio es aquella convención accesoria que insertada en un contrato de compraventa o de financiación permite que la transmisión de la propiedad de la cosa vendida al comprador no se produzca hasta que éste satisfaga íntegramente el precio convenido o, en su caso, el préstamo concedido.Este trabajo se enmarca dentro del Proyecto de Investigación de Excelencia "Contratación mercantil y Competencia empresarial: nuevas tendencias reguladoras y propuestas de conexiones normativas" (referencia DER2013-43674-P), financiado por el Ministerio de Economía y Competitividad y del que son Investigadores Principales los Profesores Miranda Serrano y Pagador López

Topological representation for monadic implication algebras

In this paper, every monadic implication algebra is represented as a union of a unique family of monadic filters of a suitable monadic Boolean algebra. Inspired by this representation, we introduce the notion of a monadic implication space, we give a topological representation for monadic implication algebras and we prove a dual equivalence between the category of monadic implication algebras and the category of monadic implication spaces.Fil: Abad, Manuel. Universidad Nacional del Sur. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cimadamore, Cecilia Rossana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; ArgentinaFil: Díaz Varela, José Patricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; Argentin

Interacting Dark Sector and Precision Cosmology

We consider a recently proposed model in which dark matter interacts with a thermal background of dark radiation. Dark radiation consists of relativistic degrees of freedom which allow larger values of the expansion rate of the universe today to be consistent with CMB data ($H_0$-problem). Scattering between dark matter and radiation suppresses the matter power spectrum at small scales and can explain the apparent discrepancies between $\Lambda$CDM predictions of the matter power spectrum and direct measurements of Large Scale Structure LSS ($\sigma_8$-problem). We go beyond previous work in two ways: 1. we enlarge the parameter space of our previous model and allow for an arbitrary fraction of the dark matter to be interacting and 2. we update the data sets used in our fits, most importantly we include LSS data with full $k$-dependence to explore the sensitivity of current data to the shape of the matter power spectrum. We find that LSS data prefer models with overall suppressed matter clustering due to dark matter - dark radiation interactions over $\Lambda$CDM at 3-4 $\sigma$. However recent weak lensing measurements of the power spectrum are not yet precise enough to clearly distinguish two limits of the model with different predicted shapes for the linear matter power spectrum. In two Appendices we give a derivation of the coupled dark matter and dark radiation perturbation equations from the Boltzmann equation in order to clarify a confusion in the recent literature, and we derive analytic approximations to the solutions of the perturbation equations in the two physically interesting limits of all dark matter weakly interacting or a small fraction of dark matter strongly interacting.Comment: 29 pages + 2 Appendices; published versio

Passions of Philology

This article suggests an approach to philology that examines the relationships between “love of language” and “love of knowledge” in the cultural context of Ancient Greece. In accordance with Plato’s view of rhetoric as an art of “psychago-gia” (soul-leading), and with Aristotle’s logic, words are conceived as symbols of the soul’s passions and the mind’s dispositional affects. These ideas have engendered an enduring tradition in the philosophy of language that extends to the philological program in Romantic Idealism, specifically Friedrich Schlegel’s project of a “philosophy of philology”, inspired by Kantian thought and its influence on subsequent methodologies and critical approaches in literary studies. Emerging from this modern tradition of critical philology is a new understanding of contemporary theories of language and literature, encompassing Jacques Derrida’s and Paul de Man’s Deconstruction, as well as the insights of Hans Ulrich Gumbrecht and Werner Hamacher.Este artículo propone una defensa de la filología que toma como punto de partida la relación entre el “amor al lenguaje” y el “amor al saber” en la cultura griega antigua. En la retórica psicagógica de Platón y en la lógica de Aristóteles la palabra es concebida como una forma de pathos, símbolo de las pasiones del alma o de las afecciones de la mente. Esta idea determina una larga tradición de filosofía del lenguaje que llega a la filología de época romántica e idealista, cuando Friedrich Schlegel proyecta una “Filosofía de la Filología” inspirada en el pensamiento kantiano, cuyos postulados fragmentarios han influido en algunas tendencias posteriores de los estudios filológicos y literarios. De esta moderna tradición de filología crítica (o filología filosófica) se deriva una nueva comprensión de las últimas teorías del lenguaje y la literatura, desde la deconstrucción de Jacques Derrida y Paul de Man hasta los recientes programas neofilológicos de Hans Ulrich Gumbrecht y Werner Hamache

Free three-valued Closure Lukasiewicz Algebras

In this paper, the structure of finitely generated free objects in the variety of three-valued closure Lukasiewicz algebras is determined. We describe their indecomposable factors and we give their cardinality.Fil: Abad, Manuel. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Díaz Varela, José Patricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; ArgentinaFil: Rueda, Laura Alicia. Universidad Nacional del Sur. Departamento de Matemática; ArgentinaFil: Suardíaz, Ana María. Universidad Nacional del Sur. Departamento de Matemática; Argentin

Root-knot nematode feeding site development is impaired by cyclin-dependent kinase inhibitors

Plant-parasitic nematodes of the genera Meloidogyne trigger the formation of giant cells that undergo recurring acytokinetic mitosis and endocycles. Expression analyses of key cell cycle genes showed their early induction in the nematode feeding site (NFS). Additionally, disturbance in NFS development and juvenile maturation were observed during treatment of infected roots with cell cycle inhibitors. Intense DNA synthesis and enlarged nuclei demonstrated that giant cells undergo additional endocycles. How precisely nematodes manipulate the cell cycle in their favour remains to be understood. A systematic comparison of the temporal and spatial expression pattern of core cell cycle genes between uninfected roots and in galls of Arabidopsis thaliana resulted in the identification of a collection of genes up- or downregulated in NFC. Among them, negative regulators are candidates to control the cell cycle in NFC. Previous work has shown that KRP2, a member of the cyclin-dependent kinase/kip-related proteins (ICK/KRP), regulate mitosis-to-endocycle transition in plant cells, and is expressed in endoreduplicating cells. The KRP2 gene showed to be expressed during gall development. Therefore to study the relevance of the KRP cell cycle inhibitor genes (7 in Arabidopis) for NFS ontogeny, mutant lines over-expressing and knocked-out are being tested to determine their effect on feeding site development. In vivo subcellular localization studies have been carried out to better understand the dynamics of these proteins during giant cell development. Based on these data, three KRP genes are perceived to control giant cell size and consequently nematode reproduction