Suma espiritual en que se resuelven todos los casos y dificutaldes que hay en el camino de la perfeccion [Texto impreso]

Sign. : *8, A-V8, X8

Environmental niche variation and evolutionary diversification of the Brachypodium distachyon grass complex species in their native circum-Mediterranean range

PREMISE OF THE STUDY: We conducted environmental niche modeling (ENM) of the Brachypodium distachyon s.l. complex, a model group of two diploid annual grasses ( B. distachyon , B. stacei ) and their derived allotetraploid ( B. hybridum) , native to the circum-Mediterranean region. We (1) investigated the ENMs of the three species in their native range based on present and past climate data; (2) identifi ed potential overlapping niches of the diploids and their hybrid across four Quaternary windows; (3) tested whether speciation was associated with niche divergence/conservatism in the complex species; and (4) tested for the potential of the polyploid outperforming the diploids in the native range. M ETHODS: Geo-referenced data, altitude, and 19 climatic variables were used to construct the ENMs. We used paleoclimate niche models to trace the potential existence of ancestral gene fl ow among the hybridizing species of the complex. KEY RESULTS: Brachypodium distachyon grows in higher, cooler, and wetter places, B. stacei in lower, warmer, and drier places, and B. hybridum in places with intermediate climatic features. Brachypodium hybridum had the largest niche overlap with its parent niches, but a similar distribution range and niche breadth. C ONCLUSIONS: Each species had a unique environmental niche though there were multiple niche overlapping areas for the diploids across time, suggesting the potential existence of several hybrid zones during the Pleistocene and the Holocene. No evidence of niche divergence was found, suggesting that species diversifi cation was not driven by ecological speciation but by evolutionary history, though it could be associated to distinct environmental adaptations.

Use of thermographic imaging to screen for drought-tolerant genotypes in Brachypodium distachyon

Thermal imaging has been used to evaluate the response to drought and warm temperatures in a collection of Brachypodium distachyon lines adapted to varied environmental conditions. Thermographic records were able to separate lines from contrasting rainfall regimes. Genotypes from dryer environments showed warmer leaves under water deficit, which suggested that decreased evapotranspiration was related to a more intense stomatal closure. When irrigated and under high temperature conditions, drought-adapted lines showed cooler leaves than lines from wetter zones. The consistent, inverse thermographic response of lines to water stress and heat validates the reliability of this method to assess drought tolerance in this model cereal. It additionally supports the hypothesis that stomatal-based mechanisms are involved in natural variation for drought tolerance in Brachypodium. The study further suggests that these mechanisms are not constitutive but likely related to a more efficient closing response to avoid dehydration in adapted genotypes. Higher leaf temperature under water deficit seems a dependable criterion of drought tolerance, not only in B. distachyon but also in the main cereal crops and related grasses where thermography can facilitate high-throughput preliminary screening of tolerant materials.

Architecture of the Nuclear Periphery of Rat Pachytene Spermatocytes: Distribution of Nuclear Envelope Proteins in Relation to Synaptonemal Complex Attachment Sites

The nucleus of spermatocytes provides during the first meiotic prophase an interesting model for investigating relationships of the nuclear envelope (NE) with components of the nuclear interior. During the pachytene stage, meiotic chromosomes are synapsed via synaptonemal complexes (SCs) and attached through both ends to the nuclear periphery. This association is dynamic because chromosomes move during the process of synapsis and desynapsis that takes place during meiotic prophase. The NE of spermatocytes possesses some peculiarities (e.g., lower stability than in somatic cells, expression of short meiosis-specific lamin isoforms called C2 and B3) that could be critically involved in this process. For better understanding of the association of chromosomes with the nuclear periphery, in the present study we have investigated the distribution of NE proteins in relation to SC attachment sites. A major outcome was the finding that lamin C2 is distributed in the form of discontinuous domains at the NE of spermatocytes and that SC attachment sites are embedded in these domains. Lamin C2 appears to form part of larger structures as suggested by cell fractionation experiments. According to these results, we propose that the C2-containing domains represent local reinforcements of the NE that are involved in the proper attachment of SCs.

Meiotic lamin C2: The unique amino-terminal hexapeptide GNAEGR is essential for nuclear envelope association

Meiotic lamin C2 is the only A-type lamin expressed during mammalian spermatogenesis. Typical for this short lamin is the unique hexapeptide GNAEGR, which substitutes the nonhelical amino terminus and part of the α-helical rod domain present in somatic lamins. Meiotic lamin C2 also lacks a carboxyl-terminal CaaX box, which is modified by isoprenylation and involved in nuclear envelope (NE) association of somatic isoforms. The mechanism by which lamin C2 becomes localized in the NE is totally unknown. Here we demonstrate that the hexapeptide GNAEGR is essential for this process: (i) Its deletion resulted in a diffuse distribution of lamin C2 within nuclei of transfected COS-7 cells; (ii) Mutated somatic lamin C, containing the sequence GNAEGR at its amino terminus, was located at the NE. The mass spectrometric analysis of the amino terminus of lamin C2 revealed that it is modified by myristoylation. Correspondingly, the substitution of the first glycine residue abolishes the NE association of lamin C2. We conclude that NE association of lamin C2 is achieved by a mechanism different from that of somatic lamins.

La comunicación intercultural: pragmática de la petición en español y en chino mandarín

Este trabajo se ha enfocado desde el plano pluridisciplinar en su primera parte, donde tratamos de la comunicación intercultural, y de la pragmática intercultural en la segunda parte, en cuanto se realiza una comparación entre la petición en español y en chino mandarín desde el punto de vista de la cortesía. Esta última acompaña, en mayor o menor grado, la realización de todos los actos de habla (Lavandera, 1988). Se ha hecho un análisis pragmalingüístico sobre los patrones que utilizan los hablantes nativos para realizar este acto en situaciones específicas, y se ha contrastado con los valores y normas culturales que fundamentan las elecciones lingüísticas de los hablantes. De este modo, y a través de esos valores y de las premisas culturales que dan cuenta de ellos, entender mejor la imagen y los deseos que los hablantes nativos tienen sobre ella para llegar a una verdadera competencia pragmática intercultural y así favorecer el entendimiento entre estas dos culturas. Consideramos que, junto al conocimiento lingüístico de los patrones de la petición, es indispensable el entendimiento de esas premisas culturales para poder realizar actos pragmáticamente correctos y evitar malentendidos. Esta es la razón por la que consideramos importante la enseñanza de estos aspectos al aprender estas lenguas. El estudio del acto de habla de la petición es particularmente interesante ya que, debido a la fuerza impositiva que implica, requiere en muchas ocasiones estrategias para mitigarla.

Idea e imagen de El Escorial en el siglo XVII: Francisco de los Santos

Esta tesis doctoral aborda el análisis crítico de una fuente literaria fundamental para el conocimiento del Real Monasterio de El Escorial durante la segunda mitad del siglo XVII: la Descripción breve del Monasterio de San Lorenzo el Real del Escorial, obra del jerónimo fray Francisco de los Santos (1617-1699), publicada por primera vez en 1657, reeditada con adiciones en 1667, 1681 y 1698, y traducida al inglés parcialmente en 1671 y de forma completa en 1760. Considerada una de las primeras y más completas guías artísticas de un monumento y sus colecciones de la Europa Moderna, su éxito editorial y difusión constituyen un caso único dentro de historia de la Literatura artística, reflejo del constante interés nacional e internacional despertado por el Real Monasterio desde su construcción. No obstante, la historia de la valoración del padre Santos como fuente para la Historia del Arte ha sido desigual, podemos decir que en su contra han jugado varios factores. En primer lugar, la permanencia de un antiguo prejuicio y desinterés hacia las adiciones barrocas de El Escorial, siendo éstas la principal novedad tratada en sus textos. En segundo, la peculiaridad del género y del estilo literario del autor: calificado de denso y prolijo, difícil de asimilar como repertorio positivo de datos y noticias y de difícil encaje en la orientación teórico-artística que ha predominado en los estudios de Literatura artística en España. En tercer lugar la incomprensión y prejuicio hacia el uso que hace el autor de sus fuentes, por una parte los textos de su predecesor como cronista: fray José de Sigüenza (1544-1606), al que retoma y resume; y por otra el uso que habría hecho de la Memoria atribuida a Diego Velázquez (1599-1660)...

The Superagency Solution

In many parts of the country, hydraulic fracturing has brought energy development onto people’s doorsteps. Efforts by local governments to employ traditional land use mechanisms to study and mitigate some of the impacts of these latest intrusions have erupted into battles over the scope of statewide agencies’ control. Forgotten in this fray are many renewable energy resources. As a general rule, they are not subject to statewide oversight, and consequently renewable energy providers must navigate the myriad of siting and permitting requirements of local jurisdictions. For several years, scholars have urged more statewide renewable energy siting procedures to level the playing field. California is the national leader in renewable energy deployment, yet its statewide energy commission does not have jurisdiction over the siting of photovoltaic solar or wind energy plants. This article explores when statewide siting is beneficial and when it may be contraindicated, making a case for consolidation of all large-scale siting under the purview of California’s “superagency,” the California Energy Commission.

Recensiones

Contiene: GARCÍA BALLESTER, Luis, Los Moriscos y la medicina. Un capitulo de la medicina y la ciencia marginadas en la España del siglo XVI, documentos por Rosa Blasco y Luis García Ballester, Editorial Labor, Barcelona, 1984, 256 pp. / Míkel de Epalza ; LÓPEZ ELUM, Pedro, Los orígenes de la cerámica de Manises y Paterna (1285-1335), Manises y Paterna, 1984, 99 páginas / Rafael Azuar ; ROSSELLÓ PONS, Margalida, Les ceramiques almohades del Carrer de Zavellà Ciutat de Mallorca. Palma de Mallorca, 1983, 159 páginas / Rafael Azuar ; TORNERO POVEDA, Emilio, La disputa de los animales contra el hombre (traducción del original árabe de «La disputa del asno contra Fray Anselmo Turmeda»), Madrid, Editorial de la Universidad Complutense, 1984, 234 pp. / Míkel de Epalza ; VÁZQUEZ DE BENITO, María de la Concepción, Muḥammad b. Abdallāh b. al-Jatīb. K. al-Wuṣūl li-ḥifz al-ṣiḥḥa fi-l-fuṣūl. «Libro de la Higiene», Salamanca, Ediciones Universidad de Salamanca, 1984, 282-182 páginas. - Commentaria Averrois in Galenum, Madrid, Consejo Superior de Investigaciones Científicas (Instituto «Miguel Asín») e Instituto Hispano-Árabe de Cultura, 1984, XII. 341 páginas / Míkel de Epalza.