Sample records for HIGOS (figs)
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1

Aplicación de Vacío en la Deshidratación Osmótica de Higos (ficus carica)/ Vacuum Application in Osmotic Dehydration of Figs (ficus carica)

Arreola, Sandra I; Rosas, Martha E
2007-01-01

Resumen en español Se determinan los coeficientes de difusión efectivos y los coeficientes de transferencia de masa para la humedad perdida y para los sólidos ganados en el proceso de deshidratación osmótica de higos (ficus carica), a tres concentraciones de sacarosa en solución (55, 65 y 75%) y dos temperaturas (35 y 45 ºC), bajo vacío constante (aprox. 40 kPa). Se consideró una geometría esférica y estado inestable, así como una cinética de primer orden. Los coeficientes de di (mas) fusión y de transferencia de materia para agua incrementaron con la temperatura y los valores mayores se obtuvieron para una concentración de 65% de azúcar y 35ºC. La concentración de la solución osmótica y la temperatura influyen considerablemente durante el proceso debido a que un aumento de esta última intensifica la eliminación de agua y la penetración de sacarosa. Además, el vacío contribuye a la apertura de la estructura del higo, disminuyendo el tiempo de proceso Resumen en inglés The aim of this work was the effective diffusion coefficients, water loss and solid gain mass transfer coefficients calculation (Dew, Des, Kw y Ks respectively) from an osmotic dehydration of figs, at three different sucrose solution concentration (55, 65 and 75%) and two temperatures (35 and 45ºC), under constant vacuum (39996.6 Pa); a spherical geometry and unsteady state was consider as well as a firs order kinetic. As a rule, the water diffusion and mass transfer coe (mas) fficients increased with temperature, and the main values were obtained for a 65% sucrose concentration and 35ºC. In this way we show the variables mentioned effect in the mass transfer and time process, which represents advantages on other dehydration operations. The osmotic solution concentration and temperature affects during process considerably owing to a temperature increase that intensify water elimination and sucrose penetration, in addition to the vacuum pressure that contribute to open the fig structure, decreasing the time process

Scientific Electronic Library Online (Spanish)

2

β-Delayed deuteron emission from 11Li: decay of the halo

Raabe, R.; Andreyev, A.; García Borge, María José; Buchmann, L.; Capel, P.; Fynbo, H. O. U.; Huyse, M.

4 pags. : 3 figs. | The deuteron-emission channel in the beta decay of the halo nucleus 11Li was measured at the Isotope Separator and Accelerator facility at TRIUMF by implanting postaccelerated 11Li ions into a segmented silicon detector. The events of interest were identified by correlating the d...

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4
5

Étude photogrammétrique de l'horloge romain de Mérida

Almagro, Antonio; Raya Román, José María
1990-01-01

Digital.CSIC (Spain)

6

Étude comparative de la fertilité des sols de bananeraies aux îles Canaries | Estudio comparativo de la fertilidad de los suelos de las bananeras en las Islas Canarias

Fernández Caldas, E.; García, V.; Gutiérrez Jerez, Francisco José; Bravo Rodríguez, J. M.

8 págs, 6 figs, 2 tabs. | Étude des différences et caractéristiques principales del sols de bananeraies des Îles Canaries. Données relatives aux influences climatiques sur ces caractéristiques pour les différentes îles et selon les versants dans chaque île. pH. CO3Ca et K présentent les plus grandes...

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7

¿Año y vez ó "año y veza"?

Hycka Maruniak, Miguel
1972-12-01

Digital.CSIC (Spain)

9

Una visión sobre el estado actual de la investigación en geomagnetismo

Torta, Joan Miquel

5 págs, 4 figs. | En este artículo se examinan los avances recientes en el ámbito general del geomagnetismo, una de las Ciencias de la Tierra con una más larga historia, seguramente por la importancia que ha tenido para la navegación. La revisión se ha dividido en cuatro grandes áreas y en diversas ...

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14

Tusculum

Dupré Raventós, Xavier

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16

Travertinos y jasperoides de Manantial Espejo, un ambiente Hot Spring Jurásico: Macizo del Deseado, Provincia de Santa Cruz, Argentina/ Travertines and jasperoids of the Manantial Espejo, a Jurassic hot spring environment: Macizo del Deseado, Santa Cruz Province, Argentina

Echeveste, Horacio
2005-07-01

Resumen en español En este trabajo se analiza el origen y las relaciones entre travertinos y jasperoides intercalados en rocas volcaniclásticas jurásicas en el distrito argento-aurífero Manantial Espejo, ubicado en el borde sur-occidental del Macizo del Deseado, provincia de Santa Cruz, Argentina. Los cuerpos de travertino constituyen estratos delgados de hasta 60 cm de espesor de calcita micrítica finamente laminada, en ocasiones con estratificación rítmica de calcita y ópalo, asoci (mas) ados a depósitos de tobas de caída y tufitas de ambiente lacustre. En algunos afloramientos, los morfotipos reconocidos revelan que la precipitación del carbonato correspondía a sectores proximales relacionados a geisers y conductos de vapor, los cuales se orientaban a los largo de las fracturas que constituyeron los canales de circulación de fluidos. La posterior silicificación de los niveles carbonáticos produjeron jasperoides que se presentan como cuerpos tabulares subverticales y subhorizontales, estos últimos con características texturales similares a aquellas de sinters. La silicificación se originó tardíamente, posiblemente durante la etapa principal del régimen hidrotermal que generó las vetas portadoras de plata y oro. Los travertinos se formaron en un ambiente de hot spring, relacionado con fracturas de un sistema de cizalla conjugado orientadas entre N 20° a 45° E y N 20° a 40° O y constituyen las evidencias más tempranas de la presencia de un régimen epitermal asociado al proceso volcánico jurásico, en un régimen tectónico distensivo, en Manantial Espejo. Resumen en inglés In the last few years, an intense mining prospecting activity for gold and silver epithermal deposits has been carried out in the Deseado Massif, Argentina. As a result, many hot spring related deposits, of possible Jurassic age, have been detected. This paper describes the mineralogical and textural characteristics as well as the facies of a group of travertine and jasperoid outcrops occurring near the silver-gold carrying lodes in the Manantial Espejo prospect (Schalamu (mas) k et al., 1998). A genetic interpretation of the deposits is done on the basis of their structural, textural, and emplacement characteristics. Their possible relationship with the epithermal mineralization is also considered. The Manantial Espejo district is located on the southwestern area of the Deseado Massif, in the middle of the province of Santa Cruz (Fig.1). The area is almost entirely covered by andesitic and rhyolithic rocks of the Bajo Pobre and Chon Aike Formations, the product of a strong, bimodal volcanic activity of Jurassic age. This volcanic event developed in a back-arc tectonic environment linked to the opening of the Atlantic Ocean (Uliana et al., 1985; Riley et al., 2001). Acidic rocks prevail in the area, consisting on high-grade ignimbrites with ash fall tuffs, tuffites, and hydroclastic breccias (Fig. 2). Among them, the chemical and biogenic carbonate and silica deposits, are present (Fig.3). The travertine mantles can be up to 0.5 m thick and, in most of cases, they overlie tuffite layers. Typically, the rock is laminated in millimetrical to submillimetrical laminae of dense, hard, non porous micritic carbonate, displaying three types of lamination: parallel sub-horizontal; stromatolithic; and, «en echelon» (possibly, a terrace facies, Fig. 4). Sometimes, the laminated structure consists of a rhythmic deposit of calcium carbonate and opal (Figs. 5 a, b), unusual association in hot spring deposits, both recent and fossil (Jones et al., 2000a; Campbell et al., 2002; Canet et al., 2005). A variety of porous travertine, dominated by small, sub-spherical and columnar growths, of the microstromatolithic or the oncoid types. The travertine layers grade laterally to siliceous laminated jasperoids (sensu Spur, 1898 and Lovering, 1972), which make sub-horizontal mantles, 0.5 to 2.0 m thick, with identical sedimentary structures as those of travertines, although they are entirely formed of chalcedony, which is interpreted as the product of replacement of calcite into silica (Fig. 6a, b). Silicification occurred at a later stage, during the intense hydrothermal alteration accompanying the formation of the quartz veins carrying gold and silver. Some jasperoid outcrops show grossly stratified, rounded surfaces with domical structures, forming banks 0.2 to 0.4 m thick, and showing a more or less concentric layout which could correspond to the silicification of bio-built algal structures (Fig. 6b). The occurrence of small vents (Fig. 6e) show the water and steam outlets. Vertical, tabular, laminated bodies, filling fractures of NE-SW strike and slip up to 1,000 m, and 3 m thick (Fig. 6f, h). They are formed of chalcedony, displaying a vertical, banded and, at times, diffuse (Fig. 6g) or breccia like structure. The morphology of the travertines and associated jasperoids in the Manantial Espejo district are compared with travertines or hot spring deposits in general, of Quaternary or Recent (Guo and Riding, 1999; Chafetz and Guidry, 2003; Hancock et al., 1999). The analogies founded allowed to reconstruct, at least in part, the depositional environment of the studied rocks (Fig. 8). The sub-vertical, tabular bodies of banded silica, would correspond to subsurface levels of fissure ridges, where erosion has generally eliminated the surface deposits with sub-horizontal stratification overlying the faults. The northernmost end of the Ayelen Oeste «vein» (Fig. 6h) would correspond to the proximal zone of the discharge channel, very close to the fissure, since part of the sub-horizontal stratification next to the fracture (zone B in Fig. 8). This area represents the most active depositional environment, where the carbonate precipitation rate is higher. Figure 6e shows a fluid outlet vent in a spring zone (zone C, in Fig. 8). The «en echelon» stratification shows very similar characteristics to those of terraces and micro-terraces occurring in modern hot springs. Micro-terraces shown in Figure 5e, found near one of the fissure crests, could correspond to those formed laterally to the outlet channels (D, in Fig. 8). As to that shown in Figure 5f, associated to travertine with sub-horizontal, parallel lamination, could correspond to that formed in the edges of pools. With regard to the parallel lamination of micritic carbonate, occurring in most of the outcrops, it may correspond to the lacustrine rims (sensu Pentecost, 1995). This type of thin lamination, forming laterally extended banks, several tens of decimeters thick, would have formed on depressed surfaces, with a distal position relative to the spring zones. The rhythmic intercalation of thin opal laminae between the calcite layers occurring in some outcrops, reveals temporary changes in the physical-chemical conditions of the mineral precipitation, possibly seasonal temperature fluctuations. Finally, the observed stromatolites and microstromatolites (Fig. 5c, g, h) indicate the presence of microorganisms in the geothermal environment. Although there is no agreement among researchers about the organic or inorganic origin of these morphotypes in geothermal environments, it is admitted that algae and bacteria induce the precipitation of calcium carbonate. The stratigraphic position of the calcareous levels identified in Manantial Espejo show that the hot spring environment began to develop early in the district, associated to an extensional tectonic regime coincident with the La Frisia or Zanjón del Pescado System (Reimer et al., 1996) which caused fracturing (direct faults) N 20° to 45º E, and N 20º to 40° W, as a consequence of aó1 located around 0°. The produced faults, made the main hydrothermal fluid circulation channels (barren) which, after reaching the surface and losing the dissolved CO2, precipitated the calcium carbonate. The migration of the maximum stress (anti clockwise, at 315°) produced a new stress field, the Bajo Grande System (Panza, 1982, 1984) generating direct faulting combined with dextral movement, at a 110° azimuth, cutting and displacing the subvertical travertine bodies. These new fluid circulation channels end up lodging the quartz veins carrying silver and gold.

Scientific Electronic Library Online (Spanish)

17

Tratamiento quirúrgico de la incontinencia urinaria de esfuerzo en nuestro medio: análisis de resultados/ Outcome analysis for surgical treatment of stress urinary incontinence in our setting

Redondo González, E.; Luján Galán, M.; Páez Borda, A.; Gómez de Vicente, J.M.; Espinales Castro, G.M.; Berenguer Sánchez, A.
2003-10-01

Resumen en español INTRODUCCIÓN: La corrección quirúrgica es actualmente el método más efectivo de tratamiento para la incontinencia urinaria de esfuerzo (IUE) de entre las diferentes opciones terapéuticas de las que se dispone en la actualidad. El objetivo de este trabajo consiste en comparar la eficacia de los distintos grupos de técnicas empleadas para el tratamiento de la IUE en nuestras pacientes. MATERIAL Y MÉTODO: Hemos llevado a cabo un análisis retrospectivo de las pacient (mas) es intervenidas en nuestro Servicio por IUE durante el periodo comprendido entre abril de 1991 y julio de 1999 (213 intervenciones en 194 pacientes), agrupando los procedimientos en 3 grupos: técnicas abdominales, técnicas abdomino-vaginales, y técnicas de cabestrillo. La tasa de éxito de la intervención fue valorada mediante tres categorías: continencia total, mejoría clínicamente significativa, y ausencia de mejoría. La comparación bivariante de proporciones se realizó mediante la prueba exacta de Fisher y el test de Chi-cuadrado. La asociación de variables cualitativas se evaluó mediante el test de Chi-cuadrado: se utilizó un modelo de Cox para el análisis multivariante de los factores predictores de continencia, y curvas de Kaplan-Meier para la evaluación de la supervivencia de la continencia post-operatoria. Para todos ellos se tomó como nivel de significación estadística una p Resumen en inglés INTRODUCTION AND OBJECTIVE: Surgical repair is the most effective option for the treatment of stress urinary incontinence (SUI) between the different therapeutical options availables at present. The main objective of our study is to compair the outcome of the different techniques employed in the treatment of SUI in our setting. METHOD: We have performed a retrospective analysis of the patients who underwent surgical intervention for SUI between 1991 to 1999 (213 surgical (mas) interventions in 194 patients) clustering the surgical procedures into three groups: abdominal, abdomino-vaginal, and sling procedures. The results of the treatment were defined as follows: total continence, significant improvement and insufficient improvement. Comparison of continence rates was performed with χ2 test and Fisher’s exact test. Association between qualitative variables was also evaluated by means of χ2 test. Multivariate analysis of predictive factors was performed with a Cox model. The outcome was also evaluated by Kaplan-Meier’s curves, and comparisons made with log-rank test. Statistical significance level was established for p

Scientific Electronic Library Online (Spanish)

18

Tracking the effects of rigidity percolation down to the liquid state: relaxational dynamics of binary chalcogen melts

Bermejo, Francisco Javier; Cabrillo García, Carlos; Bychkov, E.; Fouquet, P.; Ehlers, G.; Häussler, W.

4 pags. ; 4 figs. | The stochastic dynamics of binary liquids with formula AxB1-x, x=0–0.4 is investigated by neutron spin-echo spectroscopy. These compositions comprise samples of varying chemical connectivity, ranging from twofold-coordinated liquid Se to higher average coordinated As2S3. The para...

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19

Tolérance du bananier aux eaux bicarbonatées (eaux souterraines de Ténérife) | Tolerancia del banano a las aguas bicarbonadas subterraneas de Tenerife (Canarias)

Fernández Caldas, E.; Pérez García, V.; Borges-Pérez, Andrés

8 págs, 3 figs, 4 tabs. | Des eaux fortement bicarbonatées sont utilisées pour l'irrigation des bananeraies dans l'ile de Ténérife (Canarias). On étudie l'influence de ces eaux sur la formation éventuelle de sols salins ou alcalins. En dépit des caractéristiques chimiques de ces eaux, aucun de ces e...

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20

Thermal stability of polyethylenimine based carbon dioxide adsorbents and its influence on selection of regeneration strategies

Drage, T. C.; Arenillas de la Puente, Ana; Smith, K. M.; Snape, C. E.

9 pages, 6 figures, 5 tables.-- Printed version published Dec 2008.-- Supporting information available: Suppl. figs S1-S5. | Two approaches, thermal swing desorption over a range of temperatures and time in an atmosphere of CO2 and using nitrogen as a stripping gas at elevated temperatures, are expl...

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24

The Alvarez and Lohmann refractive lenses revisited

Barbero Briones, Sergio

15 pags. ; 10 figs. | Alvarez and Lohmann lenses are variable focus optical devices based on lateral shifts of two lenses with cubic-type surfaces. I analyzed the optical performance of these types of lenses computing the first order optical properties (applying wavefront refraction and propagation)...

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25

Targeted retrieval and analysis of five neandertal mtDNA genomes

Briggs, Adrian W.; Good, Jeffrey M.; Green, Richard E.; Krause, Johannes; Maricic, Tomislav; Stenzel, Udo

4 pages, 2 figures, 1 table.-- Supporting information available (Materials and Methods, Suppl. figs S1-S14, Suppl. tables S1-S8, Suppl refs, 1 appendix, 37 pages) at: http://science-mag.aaas.org/cgi/data/325/5938/318/DC1/1 | Sequences are deposited at the EBI (European Bioinformatics Institute) nucl...

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26

Suelos afectados por salinidad en Aragón

Herrero Isern, Juan; Aragüés Lafarga, Ramón
1988-01-01

Digital.CSIC (Spain)

27

Specificity and Plasticity of Thalamocortical Connections in Sema6A Mutant Mice

Little, Graham E.; López-Bendito, Guillermina; Rünker, Annette E.; García, Noelia; Piñón, Maria C.; Chédotal, Alain

15 pages, 9 figures.-- Supporting information (Suppl. figs S1-S3) available at: http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.1000098#toclink6 | The establishment of connectivity between specific thalamic nuclei and cortical areas involves a dynamic interpla...

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28

Specific function of phosphoinositide 3-kinase beta in the control of DNA replication

Marqués, Miriam; Kumara, Amit; Poveda, Ana M.; Zuluaga, Susana; Hernández, Carmen; Jackson, Shaun; Pasero, Philippe

6 pages, 5 figures.-- Printed version published May 5, 2009. | Supporting information (Suppl. Methods and figs. S1-S9) available at: http://www.pnas.org/cgi/content/full/0812000106/DCSupplemental | Class I(A) phosphoinositide 3-kinase (PI3K) are enzymes comprised of a p85 regulatory and a p110 catal...

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32

Reservas de potasio asimilable en suelos de Tenerife (Islas Canarias) | Available potassium reserves in Tenerife soils (Canary Islands)

Fernández Caldas, E.; Borges-Pérez, Andrés

14 págs, 8 figs, 4 tabs. | Reserves and available potassium in Tenerife soils have been evaluated. Values of ΔF were estimated in the saturated soil paste, as an index of available potassium. The levels of both reserves and available potassium are high on an absolute and relative basis.

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33

Reservas de potasio asimilable en la Isla de La Palma | Available potassium reserves in La Palma soils. Influence of parent material

Fernández Caldas, E.; Borges-Pérez, Andrés

12 págs, 4 figs, 6 tabs. | Soil reserves and available potassium in La Palma Island (Canary Islands) are studied from a chemical and geological stand point. Values of ΔF were calculated in the saturated soil paste as an index of available potassium. Depletion curves of soil potassium are studied for...

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34

Reducing power of simple polyphenols by electron-transfer reactions using a new stable radical of the PTM series, tris(2,3,5,6-tetrachloro-4-nitrophenyl)methyl radical

Torres, Josep Lluís; Carreras, Anna; Jiménez, Aurora; Brillas, Enric; Torrelles, Xavier; Rius, Jordi

7 pages, 3 figures.-- PMID: 17439176 [PubMed].-- Supporting information (Figs. S1-S13 and X-ray Crystallographic Information) available at: http://pubs.acs.org/doi/suppl/10.1021/jo062665a | Printed version published on May 11, 2007. | The synthesis and characterization of a new radical and its use f...

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35

Rare Events and Scale -- Invariant Dynamics of Perturbations in Delayed Dynamical Systems

Sánchez, Alejandro D.; López Martín, Juan Manuel; Rodríguez Díaz, Miguel Ángel; Matías, Manuel A.

Submitted on 2 Jul 2003 (v1), last revised 30 Mar 2004 (this version, v2).-- Final version to appear in Phys. Rev. Lett., 4 pages, 3 eps figs. | We study the dynamics of perturbations in time delayed dynamical systems. Using a suitable space-time coordinate transformation, we find that the time evol...

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38

Prospections archéologiques à l'ouest de la ville de Homs: rapport préliminaire campagne 2005

Haïdar-Boustani, Maya; Ibáñez, Juan José; Al Maqdissi, Michel; Armendáriz, Ángel; González Urquijo, Jesús; Teira, Luis
2005-01-01

Digital.CSIC (Spain)

40

Plátanos, fertilización y técnicas de cultivo en Canarias

Fernández Caldas, E.; Fernández-Trujillo Martínez, F.

20 págs, 6 figs, 4 tabs.-- Tít. del vol.: "Actas de la Primera Reunión Plenaria del Instituto de Edafología y Agrobiología del Consejo Superior de Investigaciones Científicas". | Incluimos en este trabajo un resumen de las observaciones y estudios experimentales realizados en Canarias en cultivos de...

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46

Nuevas aportaciones sobre las murallas y el sistema defensivo de Santa Fe (Granada)

García-Pulido, Luis José; Orihuela, Antonio

22 págs, 17 figs.-- El presente trabajo ha surgido dentro del marco de estudio que el Grupo de Investigación de Arquitectura Hispanomusulmana de la Escuela de Estudios Árabes de Granada (Consejo Superior de Investigaciones Científicas) viene realizando sobre los sistemas de fortificación defensiva c...

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47

Novel nickel resistance genes from the rhizosphere metagenome of plants adapted to acid mine drainage

Mirete, Salvador; González de Figueras, Carolina; González-Pastor, José E.

11 pages, 5 figures, 3 tables.-- PMID: 17675438 [PubMed].-- PMCID: PMC2075024.-- ISI Article Identifier: 000249969000004.-- Printed version published Oct 2007. | Supporting information (Suppl. figs S1-S2, table S1) available at: http://aem.asm.org/cgi/content/full/73/19/6001/DC1 | Full-text availabl...

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48

Nonlinear optical susceptibility of multicomponent tellurite thin film glasses

Muñoz-Martín, David; Fernández Martínez, Héctor; Fernández Navarro, José María; Gonzalo de los Reyes, José

5 pags.; 3 figs.; 2 tabs. | Tellurite (TeO2–TiO2–Nb2O5) thin film glasses have been produced by pulsed laser deposition. The dispersion of the real and imaginary parts of the linear refractive index has been measured in the range from 300 to 1700 nm. Films present high refractive index (n=2.01) and ...

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49

New aspects on Current enhancement in Brownian motors driven by non Gaussian noises

Bouzat, Sebastián; Wio, Horacio S.

11 pages, 4 figs.-- Physica A (in press). | Recent studies on Brownian motors driven by colored non Gaussian noises have shown that the departure of the noise distribution from Gaussian behavior induces an enhancement of its current and efficiency. Here we discuss some new aspects of this phenomenon...

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51

Mitochondrial apoptosis induced by BH3-only molecules in the exclusive presence of endoplasmic reticular Bak

Klee, Martina; Pallauf, Kathrin; Alcalá, Sonia; Fleischer, Aarne; Pimentel-Muiños, Felipe X.

12 pages, 7 figures.-- PMID: 19339988 [PubMed].-- Article in press. | Supporting information (Suppl. figs S1-S13) available at: http://www.nature.com/emboj/journal/vaop/ncurrent/suppinfo/emboj200990as1.html | Bak and Bax are critical apoptotic mediators that naturally localize to both mitochondria a...

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52

Mineralogía de arcillas y limos en algunos suelos volcánicos de Tenerife (Islas Canarias) | The clay and silt mineralogy of some volcanic soils from Tenerife (Canary Islands)

Rodríguez Pascual, C.; Fernández Caldas, E.; Borges-Pérez, Andrés

23 págs, 18 figs, 1 tab. | The mineralogical composition of the clay and silt fractions from volcanic materials has been studied in some soils from Tenerife (Canary Islands). The identification has been carried out by X-ray, infrared absorption and electron microscope techniques. In the clay fractio...

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54

Marcelino Menéndez Pelayo : la leyenda del millón de libros

Penadés, Honorio

4 págs, 2 figs.-- Publicado en: Mi biblioteca: La revista del mundo bibliotecario, Año III, n. 8 (invierno 2007). | [EN] Biography of Marcelino Menéndez Pelayo, Spanish scholar, librarian and writer who lived in XIX and XX centuries, remarking his love for books and reading, his particular library c...

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55

Management effectiveness of the world's marine fisheries

Mora, Camilo; Myers, Ransom A.; Coll, Marta; Libralato, Simone; Pitcher, Tony J.; Sumaila, Rashid U.

11 pages, 5 figures.-- PMID: 19547743 [PubMed].-- Supporting information (Suppl. figs. S1-S5, Suppl. text S1) available at: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000131#s4 | Ongoing declines in production of the world's fisheries may have serious ecological and socioecono...

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56

Mammalian metallopeptidase inhibition at the defense barrier of Ascaris parasite

Sanglas, Laura; Avilés, Francesc X.; Huber, Robert; Gomis-Rüth, F. Xavier; Arolas, Joan L.

5 pages, 3 figures.-- Supplementary information (SI Materials and methods, Figs S1-S7, Tables S1-S2, 13 pages) available at: http://www.pnas.org/content/suppl/2009/01/28/0812623106.DCSupplemental/0812623106SI.pdf | Printed version published on Feb 10, 2009. | Roundworms of the genus Ascaris are comm...

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57

Magnetic sensor produced by constriction.

García García, Nicolás; Rohrer, Heinrich; Muñoz, Manuel; Zhao, Y. W.
2000-04-20

Digital.CSIC (Spain)

58

Los triticales

Villena, Luis María
1964-02-01

Digital.CSIC (Spain)

60

Litología y Génesis de los depósitos del Cenozoico tardío del Bajo del Durazno, provincia de La Pampa, Argentina/ Lithology and Genesis of Late Cenozoic Deposits of Bajo Del Durazno, La Pampa Province, Argentina

Mehl, Adriana E.; Zárate, Marcelo A.
2007-12-01

Resumen en español El objetivo general del presente trabajo es analizar la litología y litofacies de los depósitos sedimentarios del Cenozoico tardío aflorantes en el Bajo del Durazno (65°10'- 65°30'O y 36°33'- 36°45'S, provincia de la Pampa) con la finalidad de inferir la génesis de estos sedimentos y comprender la historia geológica de la depresión. El Bajo, excavado en una planicie estructural conformada por depósitos de la Formación Cerro Azul (Mioceno tardío), forma parte (mas) de uno de los Valles Transversales del centro-este pampeano. En el sector oeste y austral se identificaron tres sistemas de elevaciones principales (I, II, III) y el piso del Bajo. Los depósitos sedimentarios analizados en los sistemas de elevaciones I, II y III forman una asociación de facies fluvial constituida por gravas clasto soportadas con estratificación entrecruzada planar (litofacies Gp) y estratificación tangencial (litofacies Gt), gravas macizas (litofacies Gcm), gravas matriz soportadas macizas (litofacies Gmm), arenas limosas con clastos de carbonato dispersos (litofacies Sm1) y limos arenosos macizos (litofacies Fm2). En el piso de Bajo los depósitos sedimentarios están dominados por limos arenosos macizos con estructura secundaria de fracturamiento en bloques angulares y nódulos de carbonato de calcio (litofacies Fm1), representativa de ambientes de tipo palustre. Su génesis se vincularía con procesos de decantación en áreas deprimidas y distales. Los afloramientos de esta última litofacies, situados a mayor altura topográfica, indicarían que el cuerpo de agua de tipo palustre habría tenido dimensiones variables. Los depósitos analizados apoyan sobre la Formación Cerro Azul. Tanto las sucesiones sedimentarias de las elevaciones (génesis fluvial) como las del piso del Bajo (génesis palustre) y la planicie estructural están cubiertas por un manto de arenas asignado al Pleistoceno tardío-Holoceno, correlacionable con la Formación Meaucó. La evolución del Bajo reproduce en una escala local la dinámica de un sistema de piedemonte, con sistemas de elevaciones de diferente altura relativa resultantes de ciclos de degradación-agradación. Los períodos de agradación, según sugieren los depósitos analizados, habrían estado vinculados con la acción de corrientes efímeras de baja sinuosidad de tipo entrelazado que transportaron sedimentos gravosos, arenosos y limosos desde los depósitos perimetrales del Bajo, producto del retroceso erosivo de los mismos. Resumen en inglés Bajo del Durazno (65°10' - 65°30'O y 36°33' - 36°45'S, Loventué Departament, Figs. 1 and 2) is a transitional landscape area between two major phisiographic subregions: Subregion of Hills and Meadows (Subregión de las Colinas y Lomas) and Subregion of Plateaux and Valleys (Subregión de las Mesetas y Valles,) which dominate the central-northeastern and middle-eastern part of La Pampa Province (INTA, 1980). At present Bajo del Durazno is a closed drainage system form (mas) ing a minor geomorphic unit within a regional longitudinal depression, which together with several other depressions run across an extensive structural plain. These longitudinal depressions are known as Valles transversales (Calmels, 1996). This paper reports the sedimentary characteristics of the deposits outcropping in the western part of Bajo del Durazno (Fig. 1). A lithofacies analysis approach was followed to describe and interpret the sedimentary processes involved in the accumulation of the sediments, the environment and the source area of the deposits. The general purpose is to shed light on the geological evolution of the depression. Bajo del Durazno is excavated in reddish brown sandy silts capped by a calcrete crust (Cerro Azul Formation, late Miocene) which outcrop along the southern and western margin of the depression (Figs.3 and 4). The deposits of Bajo del Durazno were studied in three main elevation systems of the western sector and the depression floor (Mehl y Zárate, 2006). The deposits outcropping in the three elevations system (I, II y III) comprise a fluvial facies association composed of clast supported gravels with planar crossbedded (lithofacies Gp); gravel with tangential crossbedded (lithofacies Gt); massive gravels (lithofacies Gcm); massive matrix supported gravels (lithofacies Gmm); silty sands with dispersed carbonate clasts (lithofacies Sm1); and massive sandy silts (lithofacies Fm2). The deposits are believed to be accumulated by ephemeral fluvial streams transporting fine sediments (suspended load) as well as bed loads (gravel and coarse sands). The variations of sedimentary structures in gravel lithofacies (Figs. 5 and 6) would reflect changes in flow hydraulic conditions. In the depression floor, the deposit consists of massive sandy silts with angular blocky fracturing and carbonate nodules (lithofacies Fm1), representing paludal- like environments (Fig. 10). The outcrops of lithofacies Fm1 located at higher topographic positions suggest a larger extension of the water body (paludal environment) prior to the accumulation of deposits in elevation system III and after the accumulation of deposits in elevation system II. Chronologically, the studied deposits are younger than the late Miocene represented by the Cerro Azul Formation and older than the eolian cover of the Meaucó Formation (Late Pleistocene-Holocene). The relative ages attributed to the sediments are based on their geomorphological location with the oldest cropping out in system elevation I and the youngest at the present floor of the depression. Geomorphologically the studied area of Bajo del Durazno reproduces a piedmont system at a local spatial scale. The elevation systems represent different piedmont levels (Mehl and Zárate, 2006), corresponding to a Bajada environment located between the flank pediments developed on the margin and the playa area (depression floor) (Fig. 11). The sediments of this bajada were deposited by ephemeral low sinuosity braided flows. These streams eroded the crust and sandy silts including carbonate nodules of the Cerro Azul Formation transporting the material from the surrounding tertiary outcrops to lower topographic positions within Bajo del Durazno (Mehl and Zárate, 2006).

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Les réserves de potassium dans les sols de bananeraies aux Canaries | Reservas de potasio en los suelos de las bananeras de las Canarias

Fernández Caldas, E.; Borges-Pérez, Andrés

6 págs, 4 figs, 4 tabs. | Eu égard aux besoins potassiques particulierement élevés du bananier, on a complété la détermination de K assimilable ou échangeable dans divers sols de Ténérife par celle de leurs réserves assimilables totales en potassium, au moyen d'extractions successives par C12Ca 0,01...

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Las sucesiones de braquiópodos en el tránsito Lías-Dogger en la Cordillera Ibérica.

García-Joral, F.; Gómez Fernández, J. J.; Goy Goy, A.; Ureta, M. S.
1990-01-01

Digital.CSIC (Spain)

66

Las nuevas plantaciones frutales

Cambra Ruíz de Velasco, Mariano
1962-07-01

Digital.CSIC (Spain)

68

Las facies Muschelkalk de Henarejos (Cuenca): sedimentología y fauna del tramo superior

López-Gómez, José; Márquez-Aliaga, Ana; Arche, A.; Goy Goy, A.
1987-01-01

Digital.CSIC (Spain)

69

Las aguas subterráneas de la Isla de La Palma. Características químicas y geoquímicas

Fernández Caldas, E.; Bravo Rodríguez, J. J.

15 págs, 6 figs, 5 tabs. | The ground waters of the Island of La Palma (Canary Islands) are studied from the chemical and geochemical standpoint. Influence of location of perched water on the chemical and geochemical characteristics is also indicated. The waters of this Island are in general of the ...

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Las aguas subterráneas de Tenerife. II. Estudios sobre el empleo de aguas bicarbonatadas | The subterranean waters of Tenerife. II. Studies on the use of bicarbonate waters

Fernández Caldas, E.; Pérez García, V.; Borges-Pérez, Andrés

15 págs, 3 figs, 4 tabs. | High bicarbonate waters are used for irrigation in the Island of Tenerife (Canary Islands). A study is made of the influence of those waters in the occurrence of saline or alkaline soils. In spite of the chemical characteristics of these waters neither of those effects wer...

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Las Secuencias Depositacionales del Plioceno-Cuaternario en la Plataforma Submarina adyacente al Litoral del Este Bonaerense/ Pliocene-Quaternary depositional sequences of the continental shelf adjacent to eastern Buenos Aires Province, Argentina

Parker, Gerardo; Violante, Roberto A; Paterlini, C. Marcelo; Costa, Irundo P; Marcolini, Susana I; Cavallotto, José L
2008-12-01

Resumen en español Se describen las características sismoestratigráficas, sedimentológicas y morfológicas del sector de plataforma submarina adyacente al este bonaerense. El trabajo se basa en los resultados obtenidos durante el desarrollo de sucesivos proyectos destinados al estudio de la cubierta sedimentaria del Plioceno-Cuaternario y reciente, utilizando metodologías de relevamiento sísmico de reflexión de media a alta resolución y muestreos de sedimentos. El sector de plataform (mas) a estudiado constituye una típica plataforma submarina silicoclástica de margen pasivo, de gran extensión y suave relieve. Su configuración morfológica está caracterizada por relieves aterrazados con una cobertura sedimentaria de depósitos arenosos relicto a palimpsestos que resultaron del retrabajamiento de sistemas costeros de playas, barreras y lagunas litorales durante el retroceso de la línea de costa como consecuencia del ascenso del nivel del mar durante la transgresión postglacial, con una etapa final de remodelado parcial durante el descenso del nivel del mar del Holoceno superior. Se diferencian dos ámbitos, la plataforma interior ("Terraza Rioplatense", entre la línea de costa y los 30/40 m de profundidad) con geoformas ajustadas a la hidrodinámica actual, y la plataforma exterior (entre la isobata de 70 m y el borde exterior de la plataforma en transición al talud), con sedimentos relicto de poca movilidad; en ambas se hallan relieves pre-transgresivos labrados en depósitos marinos y continentales del Plio-Pleistoceno que afloran bajo la cubierta sedimentaria reciente. Un escalón abrupto de 30/40 m de desnivel separa ambas plataformas. La secuencia estratigráfica estudiada está constituida por seis Secuencias Depositacionales (SD 1 a SD 6 de techo a base) que representan paquetes sedimentarios separados por discordancias. La SD 6 constituye la base de la secuencia, y corresponde a depósitos marinos del Mioceno correlacionables con las unidades costeras conocida como "Paranense-Entrerriense-Chapadmalense". La SD 5 son depósitos marinos en transición a continentales equivalentes a la Fm Barranca de los Lobos del litoral marplatense y a la unidad conocida como "Fm Puelches Equivalente" del Plioceno. La SD 4 está caracterizada por sedimentos marinos correspondientes al denominado "Interensenadense" en el litoral bonaerense, de edad aproximada a los 2,41 Ma (Plioceno superior), y se reconocen en ella diversas sismofacies de ambientes marinos, costeros y continentales con una secuencia litológica granodecreciente hacia arriba. La SD 3, marina, tiene la particularidad de tener una distribución saltuaria, a diferencia de las restantes que se extienden de manera uniforme en toda la región, lo que demuestra la ocurrencia, con posterioridad a su depositación, de importantes procesos erosivos probablemente asociados a tectónica y/o glacioeustatismo. La SD 2 representa a los depósitos marinos-costeros formados durante el estadío isotópico 5e (120 ka), que en las llanuras costeras vecinas se lo conoce como "Belgranense", y está constituida por diversas facies entre las que se destacan barreras-lagunas litorales, playas y estuarios. La SD 1 es la cobertura superficial formada durante la transgresión postglacial en ambientes de barreras-lagunas costeras-estuarios. La secuencia integrada por las SD 5 a 1 representa a las transgresiones glacioeustáticas del Plioceno- Cuaternario, con diferentes grados de preservación en la plataforma y el Río de la Plata en virtud de variantes tectónicas y morfológicas. Existe la posibilidad de que no todas las transgresiones marinas ocurridas en la región hayan quedado preservadas en el registro geológico. Resumen en inglés The Argentina Continental Shelf (ACS) is one of the largest and smoothest silicoclastic shelves in the world, condition that resulted from its geotectonic setting in a passive margin adjacent to a continental region with very extended and low-lying coastal plains. As a consequence, Pliocene-Quaternary glacio-eustatic sea-level fluctuations have been very important in its modelling and sedimentary characteristics. The study area is located between 35 and 39º S, the wester (mas) n boundary is the coastline and the eastern boundary in around 55º W that includes the outer shelf border (Fig. 1). The research is based on middle to high-resolution seismic reflection surveys and bottom/ subbottom sampling (piston cores), carried out in the context of several projects that are part of the Framework Project "Reconocimiento Geológico Geofísico del Margen Continental". The information obtained during these projects, as well as the results coming from previous projects and bibliographic compilation, allowed to gather around 4.000 km of seismic lines, 1.200 bottom samples and 92 piston cores (Fig. 2). Morphology: The ACS shows two major features (Figs. 1 and 3): inner shelf (corresponds to Terrace I, Parker et al., 1997, 1999; Violante, 2005) and outer shelf (northern part of Terrace II, Parker et al., 1997; Violante, 2005). The inner shelf extends from the coastline (or the prodelta front in the de la Plata River outlet) to the 30/40 m isobath, and includes the "Rioplatense Terrace" (RT) which represents the surface that has been modelled during the postglacial transgression but not covered by the late Holocene coastal wedge that constitutes the coastal plains. Several lower-order features modelled by the postglacial transgressive and regressive events developed on the RT surface, as the de la Plata river delta, the linear shoals systems and the La Plata Bank (Fig. 1). On the other hand, relict features composed of semiconsolidated plio-pleistocene sediments as Punta Piedras-Alto Marítimo and Restinga de los Pescadores, are significant elements in the inner shelf morphology. The outer shelf is separated from the inner shelf by a high-gradient step between 40-80 m depth (outer border of RT), which becomes, south and southeast Mar del Plata, of lower relief with a rough surface cut by transverse channels and depressions. Further east from the 80 m contourline, the outer shelf can be subdivided in two sectors: north of Querandí lighthouse it is uniformly dipping towards the shelf border, whereas in the southern part it shows a western depression (90 m depth) closer to the outer border of RT, and a eastern shoal-like elevation (75/80 m depth) near the shelf-slope transition (Fig. 3). Sedimentology: The ACS is a silicoclastic shelf where sediment characteristics and distribution are the result of dynamic, oceanographic and climatic factors. The shelf surface is covered by a relict to palimpsestic terrigenous sandy mantle which is the remnant of reworking of the deposits that constituted ancient coastal environments (barriers, coastal lagoons, estuaries) during the coastline retreat that occurred as a result of the postglacial transgressive event as well as during the sediment redistribution during the late Holocene regressive event (Urien and Ewing, 1974; Parker and Violante, 1982; Parker et al., 1999; Violante and Parker, 2000, 2004). The sandy mantle constitutes in the inner shelf a "shoal retreat massif" (in the sense of Swift, 1976) partially reworked in linear shoals systems; outcrops of the underlying plio-pleistocene substratum - partially covered by a discontinuous sheet of pebbles composed of rock fragments and caliche, beach rocks (coquinas) and sand- are common in some parts of the inner shelf. On the other hand, the outer shelf is mainly characterized by outcrops of the same substratum with minor patches of post-transgressive relict sands with a shoal-like morphology (Fig. 4). Sediment dynamic: Coastal dynamic that influenced Holocene and recent sedimentation is the result of three main sediment transport pathways: a) from the south and southeast as a consequence of the dominant oceanic circulation, that brings the relict sands stored on the shelf surface towards the coastal system, b) the regional northwards littoral transport (coastal currents) parallel to the coastline, although local inversions in the general circulation (littoral cells) are evident in the geological record, as in the Mar Chiquita Lagoon area; this transport redistributes along the coast both the shelf sands and the products of coastal erosion, c) The southwards transport of fine (muddy) sediments from the de la Plata River. Stratigraphy: The Neogene stratigraphy was defined by the application of the seismic stratigraphic method following de concepts of Mitchum et al. (1977). Six Depositional Sequences (named SD 1 to 6 from top to bottom) bounded by major seismic reflectors identified by their seismic attributes (amplitude, frequency and continuity) were recognized (Figs. 4 and 5). SD 6 (base of the sequence): corresponds to marine deposits correlated with the Miocene-Pliocene sediments known as "Paranense-Entrerriense-Chapadmalense" in the adjacent coastal areas (Parker et al., 1994, 2005). SD 5: it has seismic and sedimentological characteristics that indicate marine facies at sea changing to nearshore and fluvial facies towards the coast, and is correlated with the upper Pliocene Barranca de los Lobos Fm as well as with the Puelches Equivalente Fm defined by Yrigoyen (1975) and Parker et al. (1994). SD 4: this unit is broadly extended on the shelf with diverse seismic and litho-facies of marine, nearshore, sublittoral, low-energy coastal and continental environments, with an upwards decreasing grain-size sequence; SD 4 is equivalent to the unit known as "Interensenadense" in the adjacent coastal plains and has an upper Pliocene (2.41 Ma) age. SD 3: it is also marine/littoral and has a unique characteristic given by its discontinuous distribution in the nearshore and coastal regions as well as in some places of the shelf (Figs. 4 and 6) as a consequence of deep post-depositional erosive processes probably produced by intensification of tectonic and/ or glacioisostatic adjustments. SD 2: this unit has again a broad regional distribution, and shows different facies that represent diverse nearshore, coastal and continental environments with the particular characteristic of having been deposited as extensive barriers-coastal lagoon systems (Parker et al., 1999; Violante, 2003); it is correlated with the unit known as "Belgranense" in the adjacent coastal areas, and corresponds to the isotopic stage 5e (120 ka). SD 1: represents the uppermost sedimentary sequence formed during the last postglacial transgressive event; it is constituted by a lower transgressive system tract with different environments such as barriers/lagoons systems and estuaries, and an upper highstand system tract with regressive coastal plains, deltas and a mantle of palimpsestic and relict sands formed by reworking of the previous transgressive deposits; in most of the inner shelf surface their deposits are adjusted to the present hydrodynamic conditions (Urien and Ewing, 1974; Parker et al., 1982). Conclusive remarks: The following conclusions can be highlighted: 1) Major geomorphological features are the inner and outer shelf, which correspond to two topographically and sedimentologically different terraces separated by a step. The upper terrace (inner shelf) is a significant feature in the region which is named "Rioplatense Terrace". 2) From the sedimentological point of view, the shelf is silicoclastic; surface deposits resulted from the postglacial transgressive-regressive event. The main difference between the inner and outer shelf is given by the predominance of palimpsestic deposits in the first one and relict deposits with outcrops of the underlying Pliocene-Pleistocene substratum in the second one. 3) The Neogene stratigraphy is defined by seismicstratigraphic units representing Depositional Sequences (SD), which have been characterized on the basis of their seismic and lithological aspects and correlated with geological units known in the adjacent coastal regions. In this way it was described an uppermost, postglacial unit, followed below by a sequence of three transgressiveregressive units equivalent to the "Pampean" (Plio-Pleistocene) deposits, then a underlying unit corresponding to the "Puelches" (upper Pliocene) sands and finally the basal unit correlated with the "Paranense-Entrerriense- Chapadmalense" (Miocene-Pliocene) sequence. 4) Each SD shows a vertical sequence grading from marine (in the base) to continental (in the top) deposits in an upward decreasing grain-size distribution, therefore representing an individual and complete transgressive-regressive event. 5) The different degree of preservation of the SD in the shelf and the de la Plata River not only indicates different tectonic-glacioisostatic behaviours between both regions, but also determines the possibility that other transgressive events than those preserved in the shelf could have occurred but later completely eroded without leaving any record of their deposition.

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La teoría de redes en ingeniería de control: aplicación al análisis dinámico y al control de procesos

Taboada Antelo, Luis; Otero-Muras, Irene; Banga, Julio R.; Alonso, Antonio A.

11 págs., 11 figs. | [ES] Los procesos de la industria química, alimentaria o biotecnológica, así como muchos de los mecanismos propios de la biología de sistemas, pertenecen a la clase de los llamados sistemas de proceso. En esta contribución se hace uso de un conjunto de resultados previos que com...

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La imagen de Santa Fe (Granada) en la sillería del coro bajo de la Catedral de Toledo

García-Pulido, Luis José; Orihuela, Antonio

21 págs, 18 figs.-- Este artículo forma parte de un estudio más amplio en torno a las defensas de Santa Fe en su momento fundacional (Véase García Pulido, Luis José y Orihuela Uzal, Antonio, Nuevas aportaciones sobre las murallas y el sistema defensivo de Santa Fe (Granada)). | [ES] Las representaci...

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La iglesia de época visigoda de "Santa Lucía del Trampal", en Alcuéscar (Cáceres)

Caballero Zoreda, Luis; Almagro, Antonio; Madroñero de la Cal, Antonio; Granda Sanz, Ángel
1991-01-01

Digital.CSIC (Spain)

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La formación Puncoviscana y unidades estratigráficas vinculadas en el Neoproterozoico - Cámbrico Temprano del Noroeste Argentino/ The Puncoviscana Formation and related units in the Neoproterozoic - Early Cambrian transition of Northwest Argentina

Aceñolaza, Florencio; Aceñolaza, Guillermo
2005-12-01

Resumen en español El lapso Neoproterozoico/Cámbrico temprano en la región noroeste de Argentina se encuentra representado por una potente secuencia sedimentaria que se destaca por su escaso metamorfismo y gran tectonización. Bajo la denominación de Formación Puncoviscana (s.l.) se unifican una serie de unidades rocosas escasamente fosilíferas con esquistos, areniscas, calizas y conglomerados con amplios afloramientos en la Cordillera Oriental de las provincias de Tucumán, Jujuy y Sa (mas) lta. Si bien la secuencia fue originariamente considerada como perteneciente al "basamento Precámbrico" de la región, el hallazgo de trazas fósiles eocámbricas permitieron su reasignación cronológica posteriormente ratificada por medios isotópicos. Análisis petrológicos y geoquímicos corroboran su asignación asociada al margen continental con el desarrollo de series metamórficas de un orógeno reciclado. Paleoambientalmente se reconocen una amplia variedad de contextos sedimentarios con sectores someros dominados por oleaje, secuencias turbidíticas, facies emipelágicas y calizas que denotan variados paleoambientes en el protomargen del Gondwana. La distribución de los elementos icnológicos en las unidades de la cuenca de Puncoviscana se presenta en fajas subparalelas con un sector este caracterizado por Nereites, y un sector oeste por Oldhamia. Esta distribución espacial representaría tanto caracteres morfológicos de la cuenca como niveles temporales distintos en la evolución del mar de Puncoviscana y su biota. La presente contribución provee un análisis actualizado de la Formación Puncoviscana y las unidades vinculadas en la región, aportando nuevas lineas de evidencia sobre las ideas más recientes desarrolladas sobre la transición Neoproterozoico/ Cámbrico temprano del noroeste de Argentina. Resumen en inglés Neoproterozoic/Early Cambrian rocks are represented in northwest Argentina by a thick and heterogeneous succession of highly deformed and slightly metamorphosed sedimentary rocks. The denomination of Puncoviscana Formation (s.l.) unifies a series of rock units, represented by scarce fossiliferous sligthly metamorphosed slates, schists, carbonates, conglomerates and sandstones cropping out mostly in the Cordillera Oriental of northwest Argentina (Turner, 1960; Turner and M (mas) on, 1979; Aceñolaza et al., 1999) (Fig.1-3, 5). Originally described as the "basal Precambrian shield" of the region, it was reconsidered during the 70's by means of trace fossil associations denoting a Neoproterozoic - Early Cambrian age (Fig. 5). Integration of several lines of research as geochemistry, ichnology and stratigraphy suggest that sedimentation in the Puncoviscana Basin spanned from Neoproterozoic to the Early Cambrian (Fig. 3). The recent usage of the Siberian stages to date some strata of the Puncoviscana Formation has provoqued confusions in the literature, being highly recommended its abandonment. Siberian stages are defined by a precise set of fossils that is lacking in the strata of Northwest Argentina. Petrological and geochemical analysis corroborates a mainly authochthonous Gondwanan continental block origin (peripheral basin), with sedimentary and low grade metamorphic series developed in shallow tectonic stages of a multi-phase orogen. On the basis of general and detailed sedimentological studies, a varied spectrum of environmental settings have been recognized for the Puncoviscana basin since the 60's. Today a complex paleoenvironmental framework is understood, including shallow water wave-influenced strata, submarine fan sedimentation, hemipelagic clays and relatively deep ocean flysch-like shales and sandstones (Fig. 4). Although recent papers deny the presence of body fossils in the unit, the Puncoviscana Formation has provided two remarkable soft body fossils: Selkirkia sp. and Beltanelloides from outcrops of Jujuy and Tucumán provinces (Fig. 8). The ichnological research during the last 30 years contributed with a fairly acceptable knowledge of the paleontological content of the Puncoviscana Formation. Even though this is not a taxonomical contribution, the most obvious equivalences and synonymies are given. An updated review of the trace fossils in the Puncoviscana Formation provides the following list: Archaeonassa fossulata, Asaphoidichnus isp., Cochlichnus anguineus, Didymaulichnus lyelli, Dimorphichnus obliquus, Diplichnites isp., Glockerichnus isp., Helminthoraphe isp., Helminthopsis abeli, Helminthopsis tenuis; Helminthoidichnites tenuis, Monomorphichnus lineatus, Monomorphichnus isp., cf. Multipodichnus, Nereites saltensis (non Psamichnites saltesis, Seilacher et al., 2005), Neonereites uniserialis, N. biserialis, Oldhamia alata, O. antiqua, O. curvata, O. flabellata, O. geniculata, O. radiata, Palaeophycus tubularis, Paleophycus isp. Protichnites isp., Protovirgularia isp., Tasmanadia cachii, Treptichnus isp. Treptichnus cf. aequalternus and T. pollardi (Aceñolaza et al., 1999; Aceñolaza and Alonso, 2001; Aceñolaza, 2004) (Figs. 6-8). The geographical distribution of trace fossil assemblages display a remarkable alignment as belts, with a shallower eastwards Nereites association, and a deeper westwards Oldhamia associacion, that do not represent archetypal ichnofacies (Fig. 4) These are related to the morphology of the basin, a chronological record of the ichnofaunas, and may also represent different temporal levels on the evolution of the Puncoviscana Sea. Within the Oldhamia association most trace fossils are small sized, developed parallel to bedding planes, and bioturbation is essentially restricted to the first millimeters of strata. Deeper burrowers are recognized in the base of sandstone layers of the sequences. This spatial restriction of bioturbation with the frequent presence of wrinkle marks denotes a microbial mat related lifestyles of the fauna as it happens in other Neoproterozoic/Early Cambrian basins (Fig. 8). Within the Nereites association, a more diverse trace fossil set is recognized, with large and mid size grazing and crawling traces developed in sand-mud interfaces. Arthropod traces are common in this association. Integration of sedimentary and paleontological evidence provides remarkable elements to better understand the ecology of Late Proterozoic/Early Paleozoic biota. This contribution gives an updated analysis of the Puncoviscana Formation and related units of the region, offering new lines of evidence for the most recent ideas regarding the Neoproterozoic/Early Cambrian of NW Argentina.

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86

La dispersión de semillas del tasaigo

Pérez Padilla, David; Nieves, Concepción; Illera, Juan Carlos; Nogales, Manuel

7 págs, 4 figs, 1 tab. | La dispersión de semillas está considerada como un proceso crucial en los ciclos de vida y en la distribución espacial de las poblaciones vegetales. Estos eventos posibilitan la colonización de nuevos lugares apropiados, en los cuales las plántulas se pueden establecer y des...

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La Torre de Ambeles

Almagro, Antonio
1981-07-01

Digital.CSIC (Spain)

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La Fuente Grande de Ocaña, una posible obra de Juan de Herrera

Coppel Areizaga, Rosario; Almagro, Antonio
1977-01-01

Digital.CSIC (Spain)

92

La Formación Cerros de Aguirre: Evidencias de Magmatismo Vendiano en el Uruguay

Campal, Néstor; Schipilov, Alejandro
2005-12-01

Resumen en español Se exponen los resultados de un mapeo detallado a escala 1:20.000, petrografía y geoquímica de la Formación Cerros de Aguirre en el Dpto. de Rocha, República Oriental del Uruguay. Se trata de una unidad compuesta por una secuencia con rocas piroclásticas dominantes y algunas lavas intercaladas de geometría groseramente elíptica de unos 16 km de eje mayor y 4 km de eje menor. Se corrige el planteo anterior de Campal y Gancio (1993) mostrando ahora que la unidad est� (mas) � íntegramente apoyada sobre el basamento de alto grado en contacto normal y separada del Grupo Rocha por una discontinuidad tectónica. Las rocas piroclásticas incluyen tufos finamente bandeados, tufos masivos, lapilli-tufos y tufitas de composición variando entre composiciones andesíticas y riolíticas. Las lavas están representadas por basaltos, andesibasaltos y riolitas. Los flujos piroclásticos tienen entre 20 y 100 m de espesor y hasta 2 km de desarrollo lateral, mostrando composiciones andesíticas y riolíticas. Tanto el mapeo como la geoquímica soportan un origen cogenético para lavas y depósitos de caída. Ello permite afirmar que la única edad disponible U-Pb SHRIMP de 571 ± 8 Ma (Hartmann et al., 2002) es representativa del evento. Se exponen evidencias que sugieren que la carbonatación que afecta al paquete es concomitante con el volcanismo. La Formación Cerros de Aguirre puede representar un producto generado en un episodio extensional tardío de la orogenia Brasiliana, quizás relacionado con la generación de la cuenca en que se depositó el Grupo Arroyo del Soldado (Gaucher, 2000). Una edad más antigua, empero, es sugerida por Blanco y Gaucher (2005) para la apertura de la cuenca de Arroyo del Soldado. Independiente de la relación de estos eventos distensivos, es claro que la deformación que afecta a las vulcanitas de la Formación Cerros de Aguirre y al Grupo Arroyo del Soldado se asocia a un evento transcurrente sinistral que reactiva estructuras anteriores generadas en la etapa distensional referida. Se analizan asimismo similaridades y diferencias con otras unidades volcánicas de edad similar tanto en Uruguay como en Brasil. Resumen en inglés This paper deals with the stratigraphy, petrography, geochemistry and structural relationships of the Cerros de Aguirre Formation, which is located in the Cuchilla Dionisio Terrane in eastern Uruguay (Bossi et al., 1998; Bossi and Gaucher, 2004) (Fig. 1). Detailed mapping at 1:20,000 scale, thin section petrography and geochemistry of major and trace elements were applied in this study. The Cerros de Aguirre Formation is mainly composed of pyroclastic rocks with some inte (mas) rbedded volcanic layers, cropping out with a roughly elliptical outline 16 x 4 km in size, with a major axis oriented northsouth (Fig. 2). The Cerros de Aguirre Formation unconformably overlies granulites of the Chafalote suite (Masquelín et al., 2001). To the east, it is in tectonic contact along a regional shear zone with the greenschist-facies metasediments of the Rocha Group (Hasui et al., 1975). The Cerros de Aguirre Formation is subdivided here into three units: a) volumetrically dominant, finegrained fall deposits; b) concordant lavas, intercalated with the fall deposits, and c) pyroclastic flows. Pyroclastic rocks include finely banded tuffs, massive tuffs, lapilli tuffs and tuffites with geochemical compositions ranging from andesites to rhyolites. Lava flows are represented by basalts, andesi-basalts and rhyolites. Pyroclastic flows are 20 to 100 m thick and up to 2 km wide, showing andesitic to rhyolitic compositions. The whole assembly exhibits open folding showing N20-30E oriented, sub-vertical axial planes (Figs. 2 and 3). Deformation increases in intensity toward the east, the main structure being an asymmetric syncline truncated in its eastern flank by a shear zone that also constitutes the western boundary of the Rocha Group (Fig. 3). Geochemistry and field work, both supports a syngenetic origin for lavas and fall deposits. The pervasive carbonation affecting the unit is analyzed, showing evidences that suggest that the process is simultaneous with volcanism. Measured LOI values of up to 11.3 % are due to carbonate cementation of porous pyroclastites. Whereas this process substantially altered major element compostion of volcanic and pyroclastic rocks, their primary trace element and especially REE composition has been preserved. This is demonstrated by the absence of correlation between REE patterns (Fig. 7) and LOI or lithology. Volcanic rocks show strong compositional variation, between basalt and rhyolite, with no evident compositional gap. Basalt flows occurring at the base and top of the unit do not differ petrographically or geochemically, implying that basaltic magmatic pulses intercalated with pyroclastic rocks generated by more felsic volcanism. Two possibilities are envisaged to account for the above mentioned facts: 1) different magmatic rocks are the product of differentiation of a single source, or 2) volcanism was bimodal, but intermediate terms were generated by magma mixing mechanisms. The latter explanation is more consistent with the observed characteristics of basalts occurring at several levels in the Cerros de Aguirre Formation. Based on the syngenicity of volcanic rocks and fall deposits, available U-Pb SHRIMP ages for andesites occurring at the top of the Cerros de Aguirre Formation (571 ± 8 Ma, Hartmann et al., 2002) can be considered representative of the whole volcanic event. Regarding its geotectonic setting, the Cerros de Aguirre Formation could record a late extensional episode of the Brazilian orogeny, perhaps related to the opening of the Arroyo del Soldado basin (Gaucher, 2000), although Blanco and Gaucher (2005) argue for an older age for rifting in the latter unit. Regardless the relationship of these extensional events, deformation exhibited by both the Cerros de Aguirre Formation and the Arroyo del Soldado Group seems to be of the same age and related to a regional sinistral transpressive event.

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LOCI GENÉTICOS ASOCIADOS AL TRASTORNO BIPOLAR ESTUDIOS EN POBLACIÓN COLOMBIANA/ GENETIC LOCI ASSOCIATED TO BIPOLAR DISORDER. STUDIES IN COLOMBIAN POPULATION

OSPINA-DUQUE, J; OCHOA, L; GARCÍA, J; LÓPEZ, C; CALLE, J; CARVAJAL, L; SOTO, I; PINEDA, N; DUQUE, C; MIRANDA, A; CUARTAS, M; GOMEZ, J; AGUDELO, A; MONTOYA, G; LÓPEZ, M; GALLO, A; MONTOYA, P; PALACIO, C; BEDOYA, G; MCCARTHY, M; REUS, V; FREIMER, N; RUIZ-LINARES, A
2001-09-01

Resumen en español Objetivos: Caracterizar una muestra de familias y tríos de una población colombiana aislada para mapear loci involucrados en la vulnerabilidad al Trastorno Afectivo Bipolar tipo I (TABI). Métodos: Se recolectan tríos y genealogías utilizando las entrevistas FIGS-DIGS en miembros de las familias y posibles afectados. El poder para detectar ligamiento (PDL) se estima por simulación. El modelo utilizado asume una frecuencia para el alelo afectado de 0.003, penetrancias (mas) de 0.01, 0.81 y 0.9 y un marcador de cuatro alelos a 5cM del locus. Resultados: Se identificaron 28 familias con TAB-I, con 3.603 individuos y 160 afectados, y 246 tríos. Asumiendo homogeneidad genética y teniendo en cuenta la evidencia genética del mestizaje, las simulaciones mostraron PDL significativos de 100% para un LOD-score>3. Estamos examinando el desequilibrio promedio en tríos y tamizando en familias los cromosomas 12, 18 y 21. Conclusión: Tenemos un grupo significativo de familias y trios pertenecientes a una población aislada con un poder para detectar ligamiento al Trastorno Afectivo Bipolar. Esto permite realizar estudios de ligamiento buscando genes involucrados en la vulnerabilidad al TAB-I en población Colombiana. Resumen en inglés Objectives: To characterize a sample of families and trios from an isolated colombian population, in order to map loci involved in vulnerability to Bipolar Mood Disorder type-I (BD-I). Methods: Trios and pedigrees using FIGS-DIGS interviews to family members and possibly affected were collected. Power to detect linkage (PDL) was estimated by simulation. Model used supposes an effecter allele frequency of 0.003, penetrances of 0.01, 0.81, 0.9 and a 4-allele marker at 5cM o (mas) f the locus. Results: 28 BD-I families including 3.603 individuals and 160 affected, and 246 trios were identified. Assuming genetic homogeneity and our recently found genetic cross breeding, simulations revealed meaningful PDL of 100% for LOD-score>3. We are now assessing background unbalance in trios, and screening families for chromosomes 12,18 and 21. Conclusion: We have an informative set of BD-I families and trios belonging to an isolated population, which allow further linkage studies associated with BD-I in Colombian population.

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Informe sobre la presencia de Azolla filiculoides en el Parque Nacional de Doñana: Año 2001

Cobo García, Dolores

5 págs, 3 figs. | En abril de 2001 se constató la presencia del helecho acuático flotante Azolla filiculoides en la marisma del Parque Nacional de Doñana. Esta especie alóctona se comporta como invasora en ríos y humedales, por lo que su aparición ha causado gran preocupación y su evolución es objet...

DRIVER (Spanish)

100

Gold-Catalyzed Synthesis of Aromatic Azo Compounds from Anilines and Nitroaromatics

Grirrane, Abdessamad; Corma, Avelino; García Gómez, Hermenegildo

4 pages.-- Supplementary material available at the publisher's site: Materials and methods, figs S1-S3, table S1. | Final version of the paper available at: http://dx.doi.org/10.1126/science.1166401 | The selective formation of aromatic azo compounds at preparative or industrial levels requires stoi...

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101

Glucose uptake and its effect on gene expression in prochlorococcus

Gómez-Baena, Guadalupe; López-Lozano, Antonio; Gil-Martínez, Jorge; Lucena, José Manuel; Candau, Pedro

11 pages, 6 figures.-- PMID: 18941506 [PubMed].-- PMCID: PMC2565063.-- Supplementary information (figs. S1-S2) available. | The marine cyanobacteria Prochlorococcus have been considered photoautotrophic microorganisms, although the utilization of exogenous sugars has never been specifically addresse...

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102

Global change and species interactions in terrestrial ecosystems

Tylianakis, Jason M.; Didham, Raphael K.; Bascompte, Jordi; Wardle, David A.

13 pages, 1 figure.-- Supporting information (Boxes S1-S3, Table S1, Methods S1 and Figs. S1-S6) available at: http://www3.interscience.wiley.com/journal/121428408/suppinfo | The main drivers of global environmental change (CO2 enrichment, nitrogen deposition, climate, biotic invasions and land use)...

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103

Functional basis of protection against age-related macular degeneration conferred by a common polymorphism in complement factor B

Montes, Tamara; Tortajada, Agustín; Morgan, B. Paul; Rodríguez de Córdoba, Santiago; Harris, Claire L.

6 pages, 6 figures.-- PMID: 19255449 [PubMed].-- Supporting information (Suppl. Methods, Figs S1-S2) available at: http://www.pnas.org/content/early/2009/02/27/0812584106/suppl/DCSupplemental | Mutations and polymorphisms in complement genes have been linked with numerous rare and prevalent disorder...

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104

Fully Automated Analysis of beta-Lactams in Bovine Milk by Online Solid Phase Extraction-Liquid Chromatography-Electrospray-Tandem Mass Spectrometry

Kantiani, Lina; Farré Urgell, Marinel.la; Sibum, Martin; Postigo, Cristina; López de Alda, Miren; Barceló, Damià

Supporting information (Suppl. figs S1-S2, table S1) available at: http://pubs.acs.org/doi/suppl/10.1021/ac9001386/suppl_file/ac9001386_si_001.pdf | Article in press. | A fully automated method for the detection of β-lactam antibiotics, including six penicillins (amoxicillin, ampicillin, cloxacillin...

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105

Fotogrametría y CAD

Almagro, Antonio
1992-01-01

Digital.CSIC (Spain)

106

Fotogrametría

Almagro, Antonio; Sandoval Martín, José; Almazán Peces, Alejandro
1986-01-01

Digital.CSIC (Spain)

107

Extremely high mutation rate of a hammerhead viroid

Gago Zachert, Selma; Elena, Santiago F.; Flores, Ricardo; Sanjuán, Rafael

Supporting information (Materials and methods, figs. S1-S3, suppl. references) available at: http://www.sciencemag.org/cgi/data/323/5919/1308/DC1/1 | The mutation rates of viroids, plant pathogens with minimal non-protein-coding RNA genomes, are unknown. Their replication is mediated by host RNA pol...

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109

Estudio sobre el potasio asimilable en suelos de Tenerife y La Palma (Islas Canarias)

Fernández Caldas, E.; Borges-Pérez, Andrés; Bravo Rodríguez, J. J.

9 págs, 3 figs, 4 tabs. | Six extraction methods are compared in a study of available K in soils of Tenerife and La Palma (Canary Islands). Among the extractants, the ammonium acetate gives always the highest correlation coefficients and levels of significance when compared with the rest of the meth...

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110

Estructuras de deformación (¿sismitas?) en la Formación Río Negro, provincia de Río Negro, Argentina

Schillizzi, Roberto; Luna, Liliana; Falco, Juan Ignacio
2010-07-01

Resumen en español A Las estructuras de deformación (ED) en sedimentos blandos comprenden las alteraciones que se producen casi simultáneamente con la sedimentación. Estos procesos se hallan en relación directa con las características internas de los materiales sedimentarios y de los factores externos que actúan sobre ellos. Sus resultados incluyen deformaciones como inyecciones, fracturas, volcanes y laminaciones convolutas que afectan total o parcialmente la estratificación. Los se (mas) dimentos blandos deformados por sismos se incluyen bajo la denominación general de sismitas (seismites). Como objetivo de esta investigación se plantea reconocer, por primera vez, estructuras de deformación ubicadas en la Formación Río Negro presentes en el sector norte del Golfo San Matías, en inmediaciones del Faro Río Negro. La metodología empleada consistió en el reconocimiento y descripción de las estructuras, para lo cual se extrajeron muestras para determinar granulometría, mineralogía y contenido de materia orgánica. Se fotografiaron los distintos sectores con deformaciones con el fin de establecer modelos comparativos. El sector estudiado, de 4 km de extensión, se ubica entre el faro de Río Negro y el inicio del Banco Verde y morfológicamente corresponde a un frente acantilado con orientación ENE-OSO. En él se determinaron las siguientes ED: a- de carga simple, pseudonódulos contiguos y aislados, y estructuras complejas; b- de escape de fluidos y c- estructuras de deslizamiento basal y por presión dirigida. El origen de las deformaciones se debe a las características de las sedimentitas y a los procesos que las afectan tales como los efectos por carga, escapes de fluidos y las presiones dirigidas. Como origen de estos procesos se señalan: la presión de la columna litológica, las olas de tormentas y los terremotos. Por los rasgos hallados las deformaciones del litoral rionegrino tendrían un origen sísmico, proceso ocurrido en un único evento durante el ciclo Andino cuyos inicios se fijan hace aproximadamente 45 Ma. Por otra parte sus techos y bases no se hallan asociados a otros procesos de deformación y sus espesores no exceden el metro de potencia. Además se hallan acotadas a la zona de transición entre los miembros medio y superior de la Formación Río Negro descansando en algunos casos sobre arcilitas y en otros sobre limolitas, originadas en un paleorelieve de interdunas. Resumen en inglés Soft-sediment deformation structures (SSD) are alterations produced almost simultaneously with sedimentation. They are directly related to internal characteristics of sedimentary materials as well as to external factors acting on them. Results derived from such alterations are evidenced as injections, fractures, volcanoes and convolute laminations, among other forms, affecting stratification either totally or partially. Soft-sediment deformation structures resulting from (mas) seisms are known as seismites. The present study aims at determining for the first time the presence of SSD structures in the Río Negro Formation, located in the northern area of San Matías Gulf, near Río Negro Lighthouse, Argentina (Fig. 1). To this end, structures were firstly identified and further described. Samples were subsequently collected for the determination of grain-size, mineralogy and organic matter content. Photographs of the different sectors evidencing deformations were taken in order to determine further comparative models. Morphology in the study area is associated to cliffs with vertical, fractured fronts and with an average height of 70 m in whose base torn-down blocks are accumulated. The geological structure of the study area is related to the Cuenca del Colorado and the Comarca Nordpatagónica, whose basement is mainly composed of Paleozoic and Mesozoic crystalline rocks. The sedimentary tertiary cover from the Miocene-Pliocene is represented by light-blue sandstones of the Río Negro Formation (Andreis, 1965). This unit was formed in an aeolian environment with intercalations of clay-silt shallow lagoons and a marine episode located in the mid area of the Río Negro Formation. At the top of the Río Negro Formation there are Pleistocene-Holocene sedimentites having a thickness of up to 5 m. Within the local structural framework of our study area there are fractures with a NE-SW and a NW-SE direction, which are related with fractures N55º, N90º and N350º azimuth located in the abrasion platform. According to Dzulinsky and Walton (1965), Lowe (1975), Brencley and Newall (1977), Clauss (1993), van Loon (2002), Owen (2003), Neuwerth et al. (2006), Alfaro et al. (2006), Montenat et al. (2007), among others (Table 1), and, taking into account the geometry of deformations, laboratory reconstructions and field observations from our study area, it can be concluded that the classifications of SSD structures tend to establish morphologic and genetic systematizations. The following characteristics were identified in our study area: limited deformations among stratigraphic horizons; a lateral continuity of SSD structures at considerable distances; and a confinement between non-deformed strata and its lithological association with psamitic-pelitic sediments. The study area, which is 4 km long and is located between Río Negro Lighthouse and the beginning of Banco Verde, is from the morphological point of view, a cliffed front with an ENE-WSW orientation. Different types of SSD structures were identified in this area. For example, from the morphological point of view and according to the loading mechanisms observed, simple-load structures (Fig. 2), attached and detached pseudonodules (Figs. 3, 4 and 5) and complex structures (Fig. 6) were identified. Furthermore, from the genetic point of view and according to the intrusion processes observed in soft sediments, water-scape structures (Fig. 7) and plate- or fountain-like deformations (Fig. 8) were found. From the genetic point of view, and based on the collapse and pressure mechanisms observed, basal slumping (Fig. 9) and directed-pressure structures (Fig. 11) were also found. The above-mentioned SSD structures were analyzed and interpreted following Strachan´s model (2002) (Fig. 10) and Laird´s model (1968) (Fig. 12). The origin of SSD structures depends on the characteristics of sedimentites and on the mechanisms that produce them. In the study area, the materials susceptible to deformation come from an interdune environment that is characterized by granulometric variations derived from the fluctuating and restrictive climatic conditions (Cojan and Thiry, 1992) that typify the Río Negro Formation. Fine-grained materials having low cohesion and poor sorting such as the sediments of deformed strata (Fig. 13) produced SSD structures as a result of high pore pressure and liquefaction effects (Tsuchida and Hayashi, 1971; Obermeier, 1996). Grain packing with a porous value as that allows intercommunication among grains and saturated material, is also crucial to the formation of SSD structures. The mineralogic content of deformed levels is composed of i) quartz, chalcedony, orthose, plagioclase, pyroxenes and biotite, opaques (magnetite and ilmenite, autigenic pyrite) in crystalline aggregates; ii) undetermined Fe oxides; and iii) colorless and light-brown unaltered volcanic glass shards, clays identified as smectite-illite interstratified and scarce kaolinite. Grains are mainly subangular and, to a lesser extent, sub-round and round. The surface of the majority of grains in the study area was found clean and with some marks. The percentage of CaCO3 was found to vary from 0.5 to 3% and that of total organic carbon (TOC) was found to reach 1.5%. Deformations may be produced as a result of load deformation mechanisms, fluid escape, basal slumping or pressure-directed displacements. Due to load deformation mechanisms, structures are linked to gravity-related movements occurring during the initial stages of deposition. For these deformations to occur, grain-size at the overlaying levels should be thicker than at the underlying levels, for example, sandstones rather than silstones or claystones. These deformations are related to water saturation at the deformed level (fluidization-liquefaction). Therefore, deformation mechanisms, which involve both expulsion and rotation of fragments as well as fluid escape, are characterized by the action of lithostatic pressure which produces movement (deformation) and by the action of the underlying sedimentary levels. Deformations may also result from a fluid escape mechanism, i.e., from a mechanism associated to i) the spatial arrangement of grains (packing), ii) their shape, iii) their tendency to inequigranularity, and iv) the communication among macro- and micro- pores as well as the high or low sinuosity connection among themselves (Net and Limarino, 2000). Further requirements for deformations to occur include particular thixotrophic conditions, especially the presence of colloids among grains. The rupture of unions of particles either by hitting or by shearing is, among others, a cause which produces an unbalance between hydrostatic pressure and lithostatic pressure. If the latter is altered, the energetic unbalance makes fine sediments flow among the weakly lithified sandstones whose extrusion will occur via both vertical and horizontal pore ducts (Lopez Gamundi, 1986; Clauss, 1993). Basal slumping produces deformations that are associated not only to soft sediments deposited in natural slopes but also to interbedded sand- and mud-levels. Layers tend to have a prismatic-shaped geometry whose materials are under ductile-to-fragile conditions, in which antique layers support younger ones. Once horizontality is affected, movement, which is marked by a rupture of the original slope, begins. The lower levels are expected to transport the upper ones without affecting the original succession of layers. At the delay of movement derived from the compressive effect of the displacement front, fluids extrude forming cones or cut dikes (Fig. 10). Several deformations of this type initiate movement as result of differences in the hydrostatic gradient (Strachan, 2002). Deformations may be also produced as a result of pressure-directed displacements which are conditioned by the compaction level, thickness and ability of materials to deform. Thus, deformations occur because the original level is saturated in water as a result of the ductile behavior of materials (Bracco et al., 2005). Laird (1968) claims that SSD structures should meet some of the following requirements to be considered of seismic origin: slightly curved strata walls and floors to follow the original stratification and interruption of continuity of the stratum that is marked by a scar in which the sedimentary fillings keep their characteristics both above and below stratification. There could be rotated sediment clasts below the discontinuity as a result of a thrust-induced drag of the upper sedimentary packing. These processes could be, in turn, triggered either by the charge or pressure of the lithologic column, storm waves and seismicity. Storm-wave impact may also produce deformation in soft sediments. Nonetheless, no high energy structures such as cross-beddings or tsunami-type chaotic sedimentation were observed in our study area. Noteworthingly, for stormwave-derived liquefaction to occur, waves should reach magnitudes higher than 6 m (Alfaro et al., 2002), this being a phenomenon that was not recorded in our study area. Taken together, findings from the present study indicate that SSD structures in our study area are seismic alterations that occurred in an event during the Andean cycle whose beginnings are traced approximately 45 My ago. The fact that i) both the roofs and bottoms of these structures are not associated to other processes of deformation, ii) their thickness does not exceed one meter, and iii) they are confined to a transitional area between the middle and top members of the Río Negro Formation, lying in some cases on claystones and in some other cases, on siltstones, originated in an interdune paleorelief, confirms their seismic origin.

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Estratigrafía, Paleontología y Edad de la Formación Las Ventanas (Neoproterozoico, Uruguay)/ Stratigraphy, paleontology and age of Las Ventanas Formation (Neoproterozoic, Uruguay)

Blanco, Gonzalo; Gaucher, Claudio
2005-12-01

Resumen en español Se analiza la estratigrafía, paleontología y edad de la Formación Las Ventanas (FmLV). El área tipo de afloramiento de la FmLV corresponde a un gran sinclinal (Sinclinal del Cerro Las Ventanas) con eje buzante al S20W. Se describe la litoestratigrafía para la FmLV separándola en los siguientes miembros (de base a tope): Miembro La Rinconada, Miembro Quebrada de Viera, y Miembro El Perdido. El Miembro La Rinconada se compone principalmente de coladas basálticas y br (mas) echas volcánicas. El Miembro Quebrada de Viera se caracteriza por potentes depósitos de conglomerados polimícticos y areniscas subordinadas. El tope de la FmLV (Miembro El Perdido) lo ocupan pelitas con laminación conspicua y mostrando evidencias de ambiente disóxicos en la cima. Por primera vez se correlacionan afloramientos en torno a la ciudad de Minas con la FmLV, mostrando una evolución de facies proximales a distales de sur a norte y de oeste a este. La formación representa una secuencia grano y estrato decreciente, evolucionando de un ambiente continental dominado por abanicos aluviales a un ambiente marino somero con la ocurrencia de tempestitas. La paleopendiente fue importante, como lo indican las estructuras sedimentarias y la petrografía de conglomerados y areniscas. Una asociación de microfósiles de pared orgánica ocurre en la FmLV, a saber: Leiosphaeridia tenuissima, L. minutissima, Lophosphaeridium sp., Soldadophycus bossii, S. major, Soldadophycus sp. y Vendotaenia sp. La asociación se destaca por su baja diversidad, abundancia de Leiosphaeridia y el gran tamaño de los esferomorfos (hasta 400 µm). Se describen asimismo estructuras de biomatas (wrinkle structures) del Miembro El Perdido. En base a los microfósiles se le asigna a la FmLV una edad más probable Ediacarense (Vendiano inferior, ca. 600 Ma). La Formación Playa Hermosa puede ser una facies lateral de la FmLV, o bien encontrarse estratigráficamente por encima de la misma. De acuerdo al contenido micropaleontológico de la FmLV, se postula una cercanía temporal con el Grupo Arroyo del Soldado, posiblemente anterior al mismo. El ambiente geotectónico más probable para la FmLV es extensional, y específicamente de rift. En favor de esta hipótesis se cita el vulcanismo bimodal sinsedimentario, las fuertes paleopendientes, importantes espesores de depósitos psefíticos y la evolución de ambientes continentales a marinos. Se asocian a este evento extensional el haz de diques máficos de Nico Pérez (581 ± 13 Ma) y el Batolito de Puntas del Santa Lucía (633 ± 10 Ma), indicando que el régimen tectónico imperante en el Terreno Nico Pérez entre 633 y 580 Ma fue claramente extensional. Resumen en inglés Las Ventanas Formation (FmLV), defined and mapped by Midot (1984), is composed by a thick, finingand thinning-upward sequence covering an area in excess of 120 km² of the southern Nico Perez Terrane, Uruguay (Fig. 1). The structure in its type area corresponds to an ample syncline (Cerro Las Ventanas Syncline) with an axis oriented S20W (Figs. 2, 7f). Las Ventanas Formation is here subdivided into the following members: La Rinconada Member, Quebrada de Viera Member and E (mas) l Perdido Member (Figs. 2, 4-5). La Rinconada Member is made up of basic volcanics, mainly basalts, vulcanoclastic breccias and subordinate basic tuffs, reaching 500 m in thickness (Fig. 6). It is overlain with erosional unconformity by the Quebrada de Viera Member, which is composed by polymictic conglomerates, grading to conglomerate-sandstone intercalations up section (Fig. 7a-d). Maximum thickness reaches 3800 m. Lithoclast composition shows provenance from a mixed volcanic (basic and acid) and granitic source area (Fig. 8a-b). Whereas basalt clasts are more common at the base, rhyolitic clasts and intercalated rhyolitic tuffs occur at the top of the Quebrada de Viera Member (Fig. 5). The overlying El Perdido Member (600 m measured thickness) is characterized by laminated siltstones and shales (Figs. 7e-f, 9), showing reddish colours at the base and green and grey colours at the top. Abundant pyrite at the top of this Member indicates disoxic or anoxic conditions (Fig 7e-8d). Thus, Las Ventanas Formation represents a deepening-upward sequence, recording evolution from an alluvial fan-dominated environment to shallow marine conditions with occasional storms indicated by hummocky cross stratification at the top of Quebrada de Viera Member (Fig. 9). Petrography shows compositional and textural immaturity of conglomerates and sandstones which together with sedimentary structures point to a steep palaeorelief. Las Ventanas Formation is intruded by syenites of the Sierra de Animas Formation, which yielded a Rb- Sr age of 520 ± 5 Ma, and also by the Pan de Azúcar Granite (559 ± 28 Ma, Rb-Sr). K-Ar datings of 572 ± 7 Ma obtained for synkinematic muscovites crystallized along the Puntas del Pan de Azúcar Thrust, suggest a minimum Vendian age for the unit (Figs. 1-2). A number of organic-walled microfossils is described for the first time, namely: Leiosphaeridia tenuissima, Leiosphaeridia minutissima, Lophosphaeridium sp., Soldadophycus bossii, Soldadophycus major, Soldadophycus sp., Vendotaenia sp (Fig. 11). The assemblage is characterized by its low diversity, abundance and large size (up to 400 µm) of Leiosphaeridia. Wrinkle structures occur in the upper El Perdido Member (Fig. 9). Based on the microfossils and the available datings, we assign Las Ventanas Formation to the Ediacaran (lower Vendian, ca. 600 Ma). The Playa Hermosa Formation is in tectonic contact with Las Ventanas Formation, and can be interpreted as a lateral facies or -alternatively- be younger than the latter unit (Fig. 12). On the basis of their microfossil assemblages, we envisage that Las Ventanas Formation immediately predates the Arroyo del Soldado Group which represent a thick shelf succession deposited in the upper Ediacaran between 580 and 535 Ma. An extensional geotectonic setting, possibly a rift, is postulated for Las Ventanas Formation. In favour of this hypothesis argue the bimodal (rhyolitic and basaltic), synsedimentary volcanism, steep palaeorelief, great thickness of alluvial fan conglomerates with more than 3500 m of psephitic sediments and the evolution from continental to open marine environments. A number of magmatic units may be associated to this extensional event, including the Nico Pérez Dyke Swarm (581 ± 13 Ma) and the Puntas del Santa Lucía Batholith (633 ± 10 Ma).

Scientific Electronic Library Online (Spanish)

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Estratigrafía del Grupo Mina Verdun, Proterozoico de Minas, Uruguay/ Stratigraphy of the Mina Verdún Group, Proterozoic of Minas, Uruguay

Poiré, Daniel G.; González, Pablo D.; Canalicchio, José M.; García Repetto, Flavio
2005-12-01

Resumen en español El objetivo del presente trabajo es el de presentar un cuadro estratigráfico para las sedimentitas del área del Cerro Verdún, Minas, Uruguay. Asimismo presentar algunas consideraciones sobre sus características sedimentológicas y sus estromatolitos, a fin de discutir sus condiciones paleoambientales. En el mismo sentido, se realizan inferencias sobre la edad abarcada por estas rocas y sus potenciales correlaciones regionales. Esta sucesión ha permanecido indefinida (mas) en general, mientras que sus calizas fueron alternativamente asignadas a diversas unidades litoestratigráficas. En esta contribución se incluye al conjunto en el Grupo Mina Verdún, el cual está conformado de base a techo por: i) Formación Don Mario (40 m, base no expuesta, lutitas negras), ii) Formación La Toma (15 m, margas verdes oscuras a negras), iii) Formación El Calabozo (170 m, calizas grises, masivas, laminadas y estromatolíticas) y iv) Formación Gibraltar (60 m, techo no expuesto, dolomías en tonalidades pálidas amarillentas, verdes y rosas hasta gris oscuras más calizas rosas y pelitas y margas negras). Conglomerados polimícticos de la Formación Las Palmas cubren a esta unidad mediante una discordancia angular. En contraposición, las cuarcitas del Cerro Verdún se apoyan sobre el Grupo Mina Verdún por contacto tectónico. Las pelitas negras de la Formación Don Mario se habrían depositado en un ambiente reductor de aguas calmas. Se identifica para las mismas, de manera preliminar, un aporte desde una corteza continental superior diferenciada que sufrió una importante meteorización y retrabajo. Las margas de la Formación La Toma reflejan un cambio en la sedimentación, con un pasaje hacia un ambiente de rampa carbonática. Niveles con estromatolitos aparecen en las calizas de la Formación El Calabozo, constituidos esencialmente por columnas de laminación cónica asignables a Conophyton fm. y muy escasos estromatolitos columnares dendroides, mal preservados. Conophyton es considerado como un estromatolito submareal de aguas relativamente profundas. Esto último, sumado a la baja diversidad, sugiere un ambiente marino submareal externo para esta unidad. Correlaciones entre afloramientos locales, definirían una evolución desde una rampa carbonática hasta una plataforma, en las inmediaciones del talud de la misma. La edad de esta unidad aún no se conoce con precisión. Sin embargo, interpretaciones geológicas regionales, sobre la base de los estromatolitos presentes y de datos geoquímicos, sugieren un tiempo de depositación post-arqueano a pre-ediacareano. Resumen en inglés The aim of this contribution is to introduce the stratigraphic framework of the Mina Verdún Quarry, located in the eastern side of Verdún Hill, Minas, Uruguay (Fig. 1), and to characterise their sedimentary units. The paleoenvironments involved are outlined as well as the sedimentological significance of the very well developed stromatolites. The stratigraphic position and composition of this sedimentary succession used to be uncertain and the limestone from the Mina Ve (mas) rdún Quarry was alternatively considered part of diverse litostratigraphic units (Mac Millan, 1933; Caorsi and Goñi, 1958; Bossi et al., 1965; Midot, 1984; Preciozzi et al., 1985; Bossi and Navarro, 2000; Sánchez Betucci, 1998; Sánchez Betucci et al., 2001). From the base to the top (Fig. 2), the sedimentary succession consists of the Mina Verdún Group, Las Palmas Formation and the quartzites of the Verdún Hill (Fig. 3). Mina Verdún Group (Poiré et al., 2003b) is conformed by: Don Mario Formation (Poiré et al., 2003b): 40 m thick, base not exposed; massive and laminated, black shales (Fig 4a), which are rich in organic matter (Fig. 5a). XRD analysis shows manly quartz, with scarce calcite, clay (illite, chlorite, and IS and CS interlayer) and feldspars (Fig. 6). Applying the Bhatia and Crook (1986), Taylor and McLennan (1985) and McLennan et al. (1990, 1993) plots (Fig. 7) their geochemistry suggests a high degree of weathering and reworking in the source area compose of a differentiated upper continental crust. La Toma Formation (Poiré et al., 2003b): 15 m thick; fine-grained, dark green marls (Fig. 4b and c), bearing up to 45 % of silica and 35 % of CaCO3. Petrographically they show micritic crystals of calcite and dolomite, quartz and feldspars (Fig. 5b); lamination is interrupted by stilolytes. Clay minerals are composed mainly by illite and scarce chlorite (Fig. 6). El Calabozo Formation (Poiré et al., 2003b): 170 m thick; grey massive, laminated, and stromatolite limestones (Fig. 4d), bearing up to 93 % of CaCO3 with some collapse breccias as resulting of probably karstic phenomena. In thin section they show homogeneous mosaic of micrite and subsparite calcite (Fig. 5 c and d) with stilolites and corrugated stromatolite lamination. Very abundant calcite with rare quartz, feldspars and illite have been recorded by XRD (Fig. 6). This sedimentary sequence is affected by diagenetic features and a fragile deformation (cleavage foliation, shear zones) which are slightly hiding the stromatolite morphologies (Fig. 8), but the main features of the stromatolites from El Calabozo Formation are still well preserved. Columnar stromatolites assignable to Conophyton fm. are the most abundant group of these organic sedimentary structures. This Conophyton fm. consists of unbranching subcylindrical columnar stromatolites with strikingly conical internal laminae whose apexes define a distinctive axial zone (Figs. 10a, b, c) and their horizontal section display a conspicuously and regularly concentric structure (Figs. 10c, d, f). The internal laminae are commonly continuous from one column to another, in which case vertical sections show upward laminae apexing. Their profile is angulate to geniculate and their plant outline could be round circular to oblong, in which case the axes are strongly orientated. The attitude of the columns is usually straight but sometimes they adopt a recumbent and sinuous posture. The column height is up to 70 cm and the column width is 5 to 20 cm. However, scarce but preserved dendroid branching style stromatolites have been recorded on the field, as well as small, rounded plant outline columnar stromatolites have been observed in cores, which could represent digitate branching stromatolites. Five kilometres to the south, this stromatolitic limestone facies change to deformed laminate limestones (Figs. 4e, f). Furthermore, 40 km to south, the El Calabozo Formation bearing Conophyton stromatolites has been reported by Gaucher et al. (2004a). Gibraltar Formation (Poiré et al., 2003b): 60 m, top not exposed; black marls and shales (Figs, 10a, b, c), pink limestones and dolomite limestones, and light yellow, green, reddish, black and grey dolomites (Fig. 10d, e). The unconformity between the El Calabozo and Gibraltar formations is very irregular, which is interpreted as a karstic palaeorelief. A 4 m thick diagenetic breccia is often in the base of the unit. The Mina Verdún Group is overlaid by red polymictic conglomerates and sandstones (Fig. 10f) of Las Palmas Formation (Poiré et al., 2003b) and is intruded by a subvolcanic longitudinal (E-W) dike swarm. This shows a K-Ar whole rock datum of 485,2 ± 12,5 Ma considered as a minimum cooling (Gonzalez et al., 2004). The quarzites from the Verdún Hill are overlying these units by a tectonic contact. They have been assigned to the Cerro Espuelitas Formation by Gaucher (2000), which are Ediacarean in age. Sedimentological and stratigraphic implications The black shales and claystones of the Don Mario Formation are interpreted as fine deposits in a low energy environment with euxinic conditions, which becomes calcareous to form a carbonatic ramp (La Toma Formation). The latter shows and evolution to a carbonatic algae platform very rich in stromatolites. From a sedimentological point of view, the group Conophyton has been assigned as a deep subtidal stromatolite by Poiré (1987, 2002) based on Precambrian stromatolite cycles from Villa Mónica Formation, Buenos Aires Province, Argentina, and Logan et al. (1964) and Donaldson (1976) ideas. In this sense, the low biodiversity, Conophyton abundance and the plant view axes orientation allow to suggest a subtidal marine environment for the El Calabozo Formation, with tidal currents influence (Fig. 11). The strong dolomitization of the Gibraltar Formation and their poor exposure do not allow doing detailed interpretation about paleoenvironments. The age of the Mina Verdún Group is Precambrian but there are not major precisions about that. Unfortunately, the group Conophyton has a wide range during the Precambrian, from Early Proterozoic to Ediacarean, being impossible to define the age of these limestones. More detailed future studies about microstructure of this Conophyton could be useful to distinguish the taxonomy and to determinate its possible age. Pre-Ediacarean stromatolites have also been described 30 km to the north by Sprechmann et al. (1994) and Gaucher et al. (1996) in the Villalba Formation of the Basal Group (Gaucher y Sprechmann, 1995), but their morphologies are completely different. They have recorded stratiform, nodular-stratiform (LLH-C, LLHV) and columnar (SH-V) stromatolites associated with stromatolitic breccias, which were interpreted as intertidal to supratidal deposits. It could represent shallower stromatolite assemblages than the stromatolites from the Mina Verdún. Unfortunately, there are no radiometric data to prove this idea. Very well developed Conophyton ?ressotti and Conophyton fm. have been also recorded in the dolomites of the Villa Mónica Formation (Poiré, 1993) companied by Colonella fm., Cryptozoon fm., Gongylina fm., Gymnosolem fm., Inzeria fm., Jacutophyton fm., Jurusonia nisvensis, Katavia fm., Kotuikania fm., Kussiella fm., Minjaria fm., Parmites fm., Parmites Cf. cocrescens and Stratifera fm. (Poiré, 1989 y 1993), which radiometric age for diagenesis is 795 My (Cingolani y Bonhomme, 1988). This sequence could be correlated with El Calabozo Formation but it shows a poor biodiversity. The Mina Verdún Group is considered as a new lithostratigraphic unit in the Uruguayan stratigraphic framework, which is probably located somewhere between the Basal and Arroyo del Soldado groups.

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115

Epilepsia farmacorresistente del lóbulo temporal. Exploración con electrodos del foramen oval y resultados quirúrgicos | Pharmacoresistant temporal-lobe epilepsy. Exploration with foramen ovale electrodes and surgical outcomes

Sola, R. G.; Hernando-Requejo, V.; Pastor, J.; García-Navarrete, E.; De Felipe-Oroquieta, Javier; Alijarde, M. T.

13 págs, 11 figs, 6 tabs.-- PMID: 15999323. | [EN] [Aim] To report our experience in the surgical treatment of temporal-lobe epilepsy. [Patients and methods] An analysis was performed of the outcomes of 137 patients submitted to surgery between 1990 and 2001, with a follow-up of more than two years....

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117

El seguimiento y control de las transformaciones en regadío

Herrero Isern, Juan; Bercero Bercero, Ángel
1992-01-01

Digital.CSIC (Spain)

122

El Teatro Romano de Segóbriga

Almagro Basch, Martín; Almagro, Antonio
1982-01-01

Digital.CSIC (Spain)

125

El Cuarto Real de Santo Domingo de Granada

Almagro, Antonio; Orihuela, Antonio
1995-01-01

Digital.CSIC (Spain)

128

El Anfiteatro de Segóbriga

Almagro, Antonio; Almagro-Gorbea, Martín
1995-01-01

Digital.CSIC (Spain)

129

El Anfiteatro de Segóbriga

Almagro, Antonio; Almagro-Gorbea, Martín
1992-01-01

Digital.CSIC (Spain)

130

EYS, encoding an ortholog of Drosophila spacemaker, is mutated in autosomal recessive retinitis pigmentosa

Abd El-Aziz, Mai M.; Barragán, Isabel; O'Driscoll, Ciara A.; Goodstadt, Leo; Prigmore, Elena; Borrego, Salud

3 pages, 2 figures, 1 table.-- PMID: 18836446 [PubMed].-- Supporting information (Suppl. Methods, Suppl. Note, Suppl. Figs 1–4, Suppl. Table 1) available at: http://www.nature.com/ng/journal/v40/n11/suppinfo/ng.241_S1.html | Using a positional cloning approach supported by comparative genomics, we h...

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131

Disulfide bonds versus Trp···Trp pairs in irregular β-hairpins: NMR structure of vammin loop 3-derived peptides as a case study

Mirassou, Yasmina; Santiveri, Clara M.; Pérez de Vega, M. Jesús; González-Muñiz, Rosario; Jiménez, M. Ángeles

9 pages, 6 figures, 1 table.-- PMID: 19294654 [PubMed].-- Supporting information (Suppl. figs SF1-SF2, tabs ST1-ST2) available at: http://www3.interscience.wiley.com/cgi-bin/fulltext/122264837/sm001.pdf?PLACEBO=IE.pdf | Where a noncovalent interaction is better than a covalent bond: The most stabili...

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132

Distribución de las cromonas en la naturaleza. Cromonas del Cneorum tricoccum L.

González, Antonio G.; Fraga, Braulio M.; Pino, Oliva

23 págs, 2 figs, 2 tabs, 5 esquemas.-- Publicado en homenaje al Prof D. Manuel Lora-Tamayo. | Parte V de la serie Cromenos y cromonas. Para parte IV ver A.G. González, B.M. Fraga y O. Pino: Phytochem 13, 2305 (1974), http://digital.csic.es/handle/10261/15607 | El agrupamiento cromona se presenta con...

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133

Digital.CSIC: el desarrollo de un repositorio institucional científico en el CSIC | Digital.CSIC: Development of a Scientific Institutional Repository at the Spanish National Research Council (CSIC)

Castro, Pablo de

7 págs, 5 figs, 2 tabs.-- Contiene: Texto de la comunicación + Presentación ppt.-- Presentada en: FESABID 2009: XI Jornadas Españolas de Documentación; Sección "Experiencias profesionales" (Zaragoza, 21 de mayo de 2009). | [EN] At a time when institutional policies promoting Open Access to the resul...

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134

Developmentally Regulated Activation of a SINE B2 Repeat as a Domain Boundary in Organogenesis

Lunyak, Victoria V.; Prefontaine, Gratien G.; Núñez, Esperanza; Cramer, Thorsten; Ju, Bong-Gun; Ohgi, Kenneth A.

4 pages, 4 figures.-- PMID: 17626886 [PubMed].-- Supporting Online Material (Materials and Methods; Figs. S1 to S4; Tables S1 and S2) available at: http://www.sciencemag.org/cgi/content/full/317/5835/248/DC1 | The temporal and spatial regulation of gene expression in mammalian development is linked ...

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135

Desarrollo y validación del algoritmo de filtrado óptimo para el calorímetro hadrónico del experimento ATLAS

Poveda, Joaquín; Abdallah, J.; Castillo, M.ª Victoria; Cuenca Almenar, Cristóbal; Ferrer, Antonio; Fullana, Esteban

4 págs, 4 figs.-- Comunicación presentada en la XXXI Reunión Bienal de la Real Sociedad Española de Física y 17º Encuentro Ibérico para la Enseñanza de la Física (Granada, 10 a 14 de septiembre de 2007). | En este trabajo se muestran los estudios realizados para el desarrollo y validación del algori...

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Convergencia real y envejecimiento: retos y propuestas

Fuente, Angel de la; Doménech, Rafael

79 págs, 44 figs, 17 cuadros.-- Este trabajo ha sido preparado para la conferencia sobre "España en la UEM" organizada por el Banco de España con ocasión del décimo aniversario de la entrada en el euro. | España se enfrenta en las próximas décadas a dos grandes retos económicos y sociales: completar...

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Contribution a l'étude de la fertilité des sols de bananeraies de l'île de Tenerife

Fernández Caldas, E.; García, V.

11 págs, 3 figs, 9 tabs. | Il s'agit de l'étude des caractéristiques chimiques des sols de bananeraies de Tenerife, déterminent les niveaux de P2O5, K2O, pH, CO3Ca, matière organique, capacité d'échange, cations échangeables et pourcentages d'humidité de la pâte saturée dans les différentes zones de...

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Contribución al estudio de la fertilidad de los suelos de plátanos de la isla de Tenerife | Fertility of banana soils in the island of Tenerife

Fernández Caldas, E.; García, V.

19 págs, 3 figs, 9 tabs. | A study is made of the chemical characteristics of the banana soils in Tenerife. Determinations of P2O5, K2O, pH, CaCO3, organic matter, cation exchange capacity, exchangeable cations, and the saturated soil paste of these soils are included. | A long term experiment to st...

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Contribución al estudio de la fertilidad de los suelos de plátanos de la Isla de la Palma (Islas Canarias) | Contribution to the study of the fertility of the banana soils in the island of La Palma (Canary Islands)

Fernández Caldas, E.; Bravo Rodríguez, J. J.; García, V.

13 págs, 1 figs, 8 tabs. | The authors made a study of the chemical characteristics of the banana soils of La Palma, in relation with the climatic zones. Determinations include: P2O5, K2O, pH, CaC[O]3, organic matter, exchange capacity, exchangeable cations, and percentage of humidity of the saturat...

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Contenido en micronutrientes disponibles para las plantas de los suelos agrícolas de las medianías del municipio de Ycod

Fernández Falcón, Marino; Fernández Falcón, Teresa

22 págs, 4 figs, 3 tabs. | Teniendo en cuanta la variedad de cultivos que configuran la agricultura canaria, en este estudio se hace mayor hincapié en la viña o vid por ser una de las familias vegetales que más se está cosechando en nuestros tiempos y, dentro de todos los elementos condicionantes qu...

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141

Condiciones de formación y evolución de los suelos de Tenerife | Conditions of formation and distribution of soils of Tenerife

Fernández Caldas, E.; Guerra Delgado, A.

46 págs, 3 figs. | [EN] The conditions of formation and distribution of soils of Tenerife (Canary Islands) have been studied. According to the climatic conditions, the volcanic materials give origin to soils of the Ranker, Brown-earth-Andosoils, Alfisol, Vertisol, Saline soils and Calcic Camborthid....

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Clorosis férrica

Heras Cobo, Luis
1968-12-01

Digital.CSIC (Spain)

143

Characterization of spatiotemporal chaos in an inhomogeneous active medium

Bouzat, Sebastián; Wio, Horacio S.; Mindlin, G. B.

13 pages, 6 figs.-- Physica D (in press).-- Digital.CSIC post-print version available: http://digital.csic.es/handle/10261/7507 | We study a reaction diffusion system of the activator-inhibitor type with inhomogeneous reaction terms showing spatiotemporal chaos. We analyze the topological properties...

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Cambios en las comunidades bacterianas del rumen asociados al consumo de hojas jóvenes de roble (Quercus pyrenaica) y su posible relación con la aparición de intoxicaciones en ganado vacuno | Changes in the rumen bacterial communities associated with the consumption of young oak (Quercus pyrenaica) leaves and their possible relationship with intoxications in cattle

Belenguer, Álvaro; Hervás, Gonzalo; Doce, Raquel R.; Yáñez Ruiz, David R.; Santos, Nuria; Mantecón, Ángel R.

3 págs, 2 figs.-- Ponencia presentada a las XIII Jornadas sobre Producción Animal (AIDA. Zaragoza, 12-13 de mayo de 2009). | [EN] Intoxication of grazing cattle occurs repeatedly when they consume large amounts of young oak (Quercus pyrenaica) leaves (OL), that are rich in hydrolysable tannins (HT)....

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Cajal y sus dibujos: ciencia y arte

De Felipe-Oroquieta, Javier

18 págs, 25 figs.-- Capítulo 18 de "Arte y Neurología", Madrid: Editorial Saned, 2005. | Santiago Ramón y Cajal nació el 1 de mayo de 1852 en Petilla de Aragón, un pequeño pueblo de Navarra, y falleció en Madrid el 17 de octubre de 1934. Estudió medicina y fue profesor de anatomía e histología en la...

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Band formation from coupled quantum dots formed by a nanoporous network on a copper surface

Lobo-Checa, Jorge; Matena, Manfred; Müller, Kathrin; Dil, Jan Hugo; Meier, Fabian; Gade, Lutz H.; Jung, Thomas A.

4 pages, 3 figures.-- Supporting information (Materials and Methods, SOM Text, Suppl. figs. S1-S7, Suppl Refs, 15 pages) available at: http://science-mag.aaas.org/cgi/data/325/5938/300/DC1/1 | The properties of crystalline solids can to a large extent be derived from the scale and dimensionality of ...

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Avispas no polinizadoras asociadas a Ficus andicola (Moraceae) en la Cordillera Central de Colombia/ Non-pollinating fig wasps associated with Ficus andicola (Moraceae) in the Central Andes of Colombia

CARDONA, WILLIAM; CHACÓN DE ULLOA, PATRICIA; KATTAN, GUSTAVO
2007-12-01

Resumen en español En el interior de las inflorescencias (síconos) de los Ficus se pueden encontrar varias especies de avispas que se desarrollan. Entre estos insectos se encuentra el polinizador, que por lo general es una sola especie, mientras que las otras avispas no ofrecen ningún beneficio al árbol y por el contrario pueden producir efectos negativos sobre el número de semillas y polinizadores producidos. En este trabajo se estudió la composición de la fauna de avispas no poliniz (mas) adoras asociadas a Ficus andicola en la Cordillera Central de Colombia. Se examinaron 418 síconos que fueron recolectados de 12 árboles; las avispas que emergieron de cada uno de ellos se contaron y separaron por morfoespecies. El 46,5% de las flores de F. andicola produjeron semillas y el 53,5% avispas. Se encontraron 22 morfoespecies de avispas no polinizadoras emergiendo de los síconos de F. andicola. Las ocho más frecuentes fueron identificadas a nivel de género. Las morfoespecies más abundantes, la cuales estuvieron presentes en más del 40% de los síconos, fueron en su orden, Idarnes sp.1, Heterandrium sp. e Idarnes sp.2. La mayoría de las morfoespecies fueron encontradas en menos del 10% de los síconos. Basados en curvas de acumulación de especies las 22 morfoespecies encontradas representan el 88% de las esperadas para F. andicola. Resumen en inglés Several species of wasps may develop inside the inflorescences (figs) of Ficus spp. These species include the pollinator, usually a single species, while the other species do not provide any benefits to the tree; instead, they may affect negatively the number of seeds and pollinators produced. In this work we studied the composition of the nonpollinating fig wasp fauna associated with Ficus andicola in the Central Cordillera of the Colombian Andes. We examined 418 figs th (mas) at were collected from 12 trees; the wasps that emerged from each one were counted and separated into morphospecies. A total of 46.5% of flowers produced seeds and 53.5% produced wasps. Twenty-two morphospecies were found emerging from figs of F. andicola. The eight most abundant were identified to genus. The most abundant morphospecies, which were present in more than 40% of figs, were Idarnes sp1, Heterandrium sp. and Idarnes sp2. Most wasp species were found in less than 10% of figs. Based on species accumulation curves, the 22 morphospecies found represent 88% of the expected number of species for F. andicola.

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Aspectos sedimentológicos y estratigráficos de los depósitos cuaternarios de la costa platense del Departamento de Canelones (Uruguay)/ Sedimentologic and stratigraphic aspects of the Quaternary deposits along the Plata Coast on the Departamento de Canelones (Uruguay)

Goso Aguilar, César
2006-07-01

Resumen en español Esta contribución brinda elementos sedimentológico-estratigráficos de los depósitos cuaternarios que aparecen en los acantilados y plataformas en la costa rioplatense del Departamento de Canelones, Uruguay. Se constató la presencia de depósitos regresivos e ingresivos cuaternarios, materializados por los sedimentos pleistocénicos transicionales de la Formación Chuy y los continentales de las formaciones Libertad y Dolores, así como los transicionales holocénicos (mas) de la Formación Villa Soriano. Se caracteriza litológicamente cada unidad, se interpretan los procesos actuantes y se hacen inferencias acerca de los ambientes de sedimentación involucrados. Resumen en inglés The Uruguayan Quaternary record has been studied by several authors in the last four decades. The Quaternary glacial and interglacial record shows a few tens meters of thickness and is integrated by both sediments and non-depositional surfaces. The sedimentary package is better exposed in the southern region and coastal area of Uruguay. The non-depositional surfaces (iron crust) and paleosoils are better exposed in the north and eastern region. The Lithostratigraphic colu (mas) mn proposed by Goso (1965, 1972) focuses the Quaternary record with a precursor genetic point of view, integrating lithologic, geomorphologic and climate conditions. However, this stratigraphic proposal was partially adopted and understood by some scientists. Transitional sediments of the Pleistocene Chuy Formation and continental deposits of Libertad and Dolores formations are present. Also, transitional Holocene sediments of Villa Soriano Formation were shown and are described (Fig. 1). The goal of this paper is to contribute to the knowledge of a part of this record especially towards some sedimentologic and stratigraphic features of the Quaternary deposits exposed along Rio de la Plata coast in the Canelones Department, Uruguay (Figure 2). The Chuy Formation is very well exposed in Villa Argentina and Las Vegas - La Floresta beaches. It is integrated mainly by white conglomerates and coarse to fine sandstones with current and wave traction structures and trace fossils. Also contains fossiliferous green clay deposits. It looks with variable thickness since a few meters to twenty five meters (Figs. 3 and 5). It was deposited during an interglacial period in transitional sedimentary environment, predominantly the shoreface portion in a barrier island and lagoon systems, into tidal conditions. The top of this lithofacies sequence shows a thin (few centimetres) iron crust in the area. This non-depositional surface was also observed in others inner Canelones localities (several Santa Lucia river sections). The Libertad and Dolores Formations can be observed in several localities along the studied area. They are composed mainly of brownish fangolites and silt-clay sediments. Massive, parallel lamination, incised lobes and tabular deposition are the main structures and geometries exposed of these units (Figs 4-8). They were deposited during a Pleistocene glacial period with the alternance of semiarid and temperate conditions and materialize a continental sedimentation (gravity flows, reworked eolian deposits). These units show a few meters of thickness. The Villa Soriano Formation is present in La Floresta beach, Sarandí creek mouth, and is composed mainly by grey fangolites and black fossiliferous clays containing molluscs valves (Figs 3e and 9). This unit was deposited during the current interglacial period and materializes the last ingressive sea-level conditions. Considering both the coastal outcrops and subsurface distribution in Uruguay the Villa Soriano Formation represents the last holocenic embayments and shorelines. The thickness of this unit in the area is less than six meters. The coast of Canelones Department along Río de la Plata shows several meters of quaternary sequences in many locations. In these combined sections two transgressive-regressive cycles were observed and analyzed. The former is composed by sediments of the Libertad II (continental) and Chuy III (transitional) Formations deposited since Medium to Upper Pleistocene, while the latter is constituted by a few meters thickness of sediments that belongs to both Dolores (continental) and Villa Soriano (transitional) formations during the time interval Upper Pleistocene - Holocene.

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150

Aspectos generales de la biodiversidad en los ecosistemas marinos y terrestres

Jaume, Damià; Duarte, Carlos M.

16 págs, 7 figs. | Los océanos son el bioma más grande de la Tierra. Con 361 millones de km2 y una profundidad media de 3.730 m, cubren el 71% de la superficie planetaria. Además, han sido el escenario primigenio de la diversificación de la vida. Así, los primeros fósiles conocidos corresponden a es...

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Arquitectura y paleoambientes de los depósitos fluviales gravosos de la Formación Las Cumbres (Neógeno), en Villa Mervil, La Rioja, Argentina/ Architecture and paleoenvironment of the fluvial gravel deposits of Las Cumbres formation (neogene), Mervil Village, La Rioja, nw-Argentina

Bossi, G.E.; Georgieff, S.M.; Vides, M.E.
2007-07-01

Resumen en español Un corte de la ruta nacional 60, 500 m al oeste de Villa Mervil (Sierras de Mazán, La Rioja) muestra el contacto entre las Formaciones Salicas y Las Cumbres, con excelente exposición de la arquitectura fluvial que pudo ser extendida en tres dimensiones y por más de 700 m en sentido N-S, a ambos lados de la ruta. El corte muestra el contacto entre las Formaciones Salicas (Plioceno) y Las Cumbres (Plio-Pleistoceno). Pueden ser reconocidos cinco estadios de sedimentación (mas) : A-S, el inferior, constituido por areniscas friables fluviales y eólicas; F, de capas tabulares consistentes en limos de barreal y areniscas de planicie de distributarios (escorrenteras y barras efímeras) con abundantes calcretos y rizoconcreciones; B, el mejor preservado y que ha permitido el análisis 3D, de conglomerados arenosos, que corta profundamente los dos estadios inferiores. El Estadio B está organizado en una serie de mesoformas de canal, con barrancas izquierdas (al Oeste) bien definidas. En su etapa final de abandono (Estadio L), fue rellenado por capas tabulares de arenas finas limos pardos, que contienen una arcilita verde y una capa de micrita blanca, que pueden asignarse a un depósito lacustre somero. Finalmente yace sobre todo el conjunto anterior, el Estadio C, de conglomerados finos arenosos que forman un extenso sistema de canales y planicie aluvial pero mal representado en estos afloramientos. Las particularidades de estos depósitos pueden ser comparadas con expresiones locales del ambiente actual: el río Pituil (al oeste de la Sierra de Velasco) la llanura arenosa del Bolsón de Pipanaco y el barreal del Señor de la Peña, donde impera un clima árido con una escasas lluvias estivales, indicado condiciones climáticas similares. Resumen en inglés A cut along the National Road 60, 400 m west of the Mervil Village, a small town located at the southern end of the "Bolsón de Pipanaco" (Pampean Ranges of NW-Argentina) unveils a 3-D fluvial and eolian architecture in beds that belong to the stratigraphic passage between the Salicas (Pliocene) and Las Cumbres (Plio- Pleistocene) Formations (Fig. 1 and 2). Fossil mammals found in the Salicas Formation belong to the Huayquerian fauna that could be dated in the Pliocene (B (mas) ossi et al., 1996). A four-fold classification of contacts hierarchy (Allen, 1983) was used to define individual sedimentary bodies and their associations: order 0, are the contacts between laminas within a laminaset; order 1 are the contacts between laminasets (represented by parallel or crossbedded cogenetic packages); order 2 contacts, cut order 1 contacts and embrace bedded packages or storeys, limited themselves by order 1 contacts, that show a similar genetic emplacement (similar features in outcrops); finally the order 3 contacts, cut and embrace sedimentary bodies limited by order 2 contacts, defining major groups or stages. Five distinct stages were recognized (Fig. 3): a lower A-S stage, covered by an extended floodplain F stage, cut deeply by the gravelly stage B, partially filled by L stage, and covered by the fluvial gravelly C stage at top (Fig. 4 and 5). The sandy A-S stage consists of channel and sandflat deposits formed by alternating fluvial (A) and eolian (S) storeys. Facies assamblage "A" is an association of 9 storeys (Fig. 3) composed of moderate sorted massive or cross-bedded sandstones, with few subrounded pebbles (schists and granites) in or near their concave bases. Most of the A storeys bottoms, are covered by a 1-5 cm thick silty shale drapes slightly disturbed or forming clay galls partially curled and/or removed (Fig. 4b and c). The facies assemblage S, is an association of 6 storeys (painted white in Fig. 5b and c) formed by well-sorted fine to medium size sandstones with occasional mud intraclasts (pebble sizes, not eolian materials probably incorporated by gravity collapse or sudden water sheets). The meter thick silty "F1" storey (Fig. 4 b and e) is composed of 10 to 11 tabular decimeter slightly endurated beds, interpreted as playa lake ("barreal") deposits by comparation with very similar sediments that fill the nearby barreal "El Señor de la Peña" a typical endorheic depression. This "F1" horizon is the source of most irregular blocks found at the foot of the left margin bank cuts of the B stage. The F2 storey (Figs. 3 and 4b) is composed of 0.90 m tabular to lenticular coarse sandstone horizon crowded of calcretes and rhyzoconcretions defining a paleosol horizon. The F3 storey is also composed of massive to crossbedded ill-sorted pebble coarse sandstones. Both F2 and F3 storeys were deposited by sudden floodings not conected to visible channel locations. The F3 storey is not related with the F2 storey calcretization. There are six irregular and lenticular storeys in the "B" stage, defined by concave and convex stratification designs. These storeys could be considered mesoforms in the sense of Bridge (1985, 1993) of the macroform "B". A close correlation of the contacts shown in the two walls of the road cut associated with contact orientation measurements and paleocurrents, allowed to built models of the 3D situation in several evolution steps starting with storey B2 ending up in storey B6 (Figs. 6 a-c). The B channel stage is deeply incised on the F and A-S stages indicating a change of the equilibrium profile. The B stage itself, represented by storeys B5 and B6, were mapped beyond the road cut for an extension of 700 m (in N-S sense) yielding a map that shows a NE-trending low sinuosity river with cut banks, lateral bar deposits, overbank deposits deposits with variable width.The last block (Fig. 6d) shows the abandon "L" stage of lacustrine fillings (see Fig. 3 for stratigraphy relations and Fig. 4 for details), composed of at leat four storeys, three of them (L1, L2 and L3) are fillings of the central part of the pond and a fourth (L4) a clinoform, is a lateral deposit. The stage C outcrops at the top of the wall cuts covering though a third order contact, the stages F, L and B. It is composed of fine to medium size fluvial gravels without visible bank cuts. The very limited lateral and vertical exposures preclude it, from a further discussion. Most paleocurrent measurements were taken in the axis of concave structures (crossbeddings) and the points where the order 2 contacts merge into the basal order 3 contact. The point of merging of the order 2 and 3 contacts in convex stratified bodies, indicates the position of the bar structure, the paleocurrents at their bases show the local direction of the bar slope in this particular stage of growing (Fig. 7). Converging or diverging paleocurrent patterns at the outcrop face combined with vertical textural variations, unveil the position of the outcrop cut in relation to the hidden 3D structure. Most of the mapped architectural features yielded also paleocurrents measurements on cross-bedding and pebble imbrications that were integrated with the textural and structural evidences (Fig. 9). The scheme of Fig. 7 was used in the model of Fig. 9 to position the bar designs on the plan. The model of Fig. 9b, is a cartoon of a slightly ondulate landscape crossed from SSW to NNE by the B stage river channel. Fig. 8 shown the succesive bank cuts created by the B stage channel during its migration to west. Calcretes and rhizoconcretions over convex or tabular gravels storeys, mapped as inside features of channel "B", indicate an ephemeral regime with riparian vegetation (Fig. 9). The Pituil River (Fig. 10) draining the northwest end of the Velasco Range and the sandy plains located north of the Mazán Range and near the center of the "Bolsón de Pipanaco" were used as modern analogs of the ancient Mervil channel system (stages B and A-S respectively). The structural details shown by the Salicas Formation at the Mervil area around the road cut, are also present in the modern analogs, indicating a similar arid climate.

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Ardilla Moruna Atlantoxerus getulus (Linnaeus, 1758)

López-Darias, Marta

6 págs, 4 figs, 2 tabs. | La ardilla moruna (Atlantoxerus getulus), única especie actual de su género, es originaria del noroeste de África (Marruecos y algunas zonas de Argelia). En 1965, una pareja adquirida en Sidi Ifni fue introducida en la isla de Fuerteventura, Islas Canarias, como animal de c...

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Análisis de facies y paleoambiental de alta resolución de la Aloformación Punta San Andrés (Plio-Pleistoceno), provincia de Buenos Aires, Argentina

Beilinson, Elisa
2009-07-01

Resumen en español La Aloformación Punta San Andrés aflora principalmente a lo largo de las barrancas costeras que se desarrollan desde la ciudad de Mar del Plata hasta la ciudad de Miramar y comprende las sedimentitas de edad plio-pleistocenas interpretadas como depósitos continentales de planicies aluviales, sistemas fluviales de baja sinuosidad y cuerpos de agua someros. El presente trabajo tiene por finalidad efectuar un análisis de alta resolución de facies sedimentarias así como (mas) de asociaciones de facies y arquitectura de los cuerpos sedimentarios presentes en los afloramientos de Baliza San Andrés y Complejo Turístico Chapadmalal de la Aloformación Punta San Andrés con el propósito de elaborar un modelo conceptual y dinámico de los ambientes depositacionales que la conformaron. Basado en el trabajo de campo y de laboratorio realizado, se definieron en primera instancia dos grandes grupos de facies, unas de origen depositacional y otras de origen postdepositacional, las cuales se agruparon en cuatro asociaciones de facies según los procesos que le dieron origen y según su arquitectura (AF I a IV: canales fijos de baja sinuosidad, canales móviles de alta sinuosidad, lóbulo de explayamiento y planicie de inundación pedogenizada). El análisis de estas asociaciones permitió definir ambientes depositacionales cuya sucesión e interrelación permite inferir un cambio progresivo en las condiciones de acomodación y paleoclimáticas imperantes durante su desarrollo. Resumen en inglés The continental deposits of the Punta San Andrés Alloformation (Plio-Pleistocene) crop out in the marine cliffs of south eastern Buenos Aires province (Fig. 1). The deposits of this unit have been assigned to different continental sub-environments such as floodplains, fluvial channels and temporary water bodies (Zárate, 1989). The aim of this work is to perform a high-resolution facies and facies association analysis as well as an architectural characterization of the s (mas) edimentary bodies cropping out in Baliza San Andrés and Complejo Turístico Chapadmalal (Fig. 1). This information will be used to elaborate a conceptual and dynamic model of the depositional environments present in the Punta San Andrés Alloformation and to define main controlling factors over its accumulation. The study area is located in a typical passive margin controlled by transversal extensional systems that originated rift basins (aulacogens) with very little basaltic magmatism (Ramos, 1996; Parker et al. 2008). This area experienced block rotation due to isostatic equilibrium and sedimentary overload. Accumulation of post-Miocene deposits was favored by a high sedimentary dynamic associated with the rise of the Andean Cordillera (Turic et al. 1996; Parker et al. 2008). More specifically, the study area is located in the southeastern part of the Tandilia Geological Province (Rolleri, 1975, Fig. 1). The pioneer papers on stratigraphy of the Mar del Plata and Miramar marine cliffs were carried out by Ameghino (1908), Frenguelli (1921) and Kraglievich (1952, 1953, 1959) (Figs.2, 3). The sedimentological characterization of these deposits was made by Teruggi et al. (1956) and Zárate (1989). This last author also proposed an allostratigraphic framework which intended to unify and simplify the late Cenozoic stratigraphy (Fig. 2). The rich vertebrate fauna present in the Punta San Andrés Alloformation and related units was studied since the first contributions by Ameghino (1908). These studies were the basis for the South American Late Cenozoic biostratigraphic scheme (Fig. 2; Marshall, 1985; Cione and Tonni, 1995, 1999). According to Zárate (1989), the Punta San Andrés Alloformation unconformably overlays the Pliocene continental deposits of the Punta Martínez de Hoz, Playa Los Lobos and Playa San Carlos alloformations. Its lateral extent is about 15 km from the Arroyo Lobería to Punta Vorohué (Fig. 1) and it also crops out between Arroyo Lobería and Playa San Carlos (Fig. 1). The mean thickness of the Punta San Andrés Alloformation is 15 meters. Internally, it is subdivided into three allomembers limited by discontinuity surfaces with a lateral extent that allows mapping them at 1:25.000 scale (Zárate, 1989; Fig. 2). Because of the high mineralogical and textural homogeneity (silty sand and reworked loessoid silt) of the cenozoic deposits in the study area (Teruggi et al., 1956) the discrimination amongst the different units is based on the abundance of the channelized facies, the carbonatic precipitation and the degree of development and maturity of paleosoils (Zárate, 1989). During field work 10 detailed, 1:50 scaled sedimentological profiles were made at Baliza San Andrés and Complejo Turístico Chapadmalal (Fig. 1) from which the 4 more complete are shown in figure 4. All stratigraphic logs were described in detail and focus was made in grain size, lithology, primary sedimentary structures, bioturbation, fossil content, scale and geometry of the lithosomes; all of these useful features to define sedimentary facies (Reading and Levell, 1996). The abundance of post depositional features (mainly pedogenetic) in the Punta San Andrés Alloformation made necessary the subdivision of sedimentary facies into two groups: depositional and post-depositional. The depositional facies were classified and described according to Miall´s scheme (1978, 2006), which was modified to facilitate their description and interpretation (Table 1). The post-depositional carbonatic facies were described according to Zárate´s scheme (1989) in which the studied features are the geometry of the calcareous accumulation (development in one, two or three dimensions), internal structure, hardness, abundance and lateral extent. The analysis of the seven depositional facies (Table 1) led to interpret a continental environment where unidirectional streams allowed the migration of 3D and 2D dunes as well as the lateral migration of side bars (facies Cig, ACt, ACs, Ah and Ae). It also made clear the presence of paleosoils developed on sheet-flood or splay deposits (facies Alp) and of suspension-related sediments (facies Pm). The analysis of the three post-depositional facies (Table 1) led to the identification of carbonatization processes related to pedogenesis (facies Bc and Tm) and to diagenesis in a vadose environment (facies Tp). The sedimentary facies were grouped into four facies associations (FA; Table 2). Facies associations I and II are related to fluvial channels and FA III and IV are related to floodplains. In the first group, fixed, lowsinuosity channels were differentiated from mobile, high-sinuosity channels based on their symmetric, simple ribbon geometry (Friend et al. 1979; Gibling, 2006) and their constituent facies (Cig, ACt and Ae) as opposed to multiepisodic, complex ribbons (Friend et al., 1979) with participation of Cig, ACt, ACs, Ah and Ae facies. The floodplain associations were divided in crevasse-splay and calcic paleosoils associations. The first one is composed of Alp facies, has a wedge-like geometry, a coarsening-upward arrangement, laterally related to fixed, low-sinuosity channels and a lateral extension over 3 kilometers (Figs. 10a, b). The former is mainly composed of Tp and Tm facies, has a tabular geometry, also laterally related to fixed, low-sinuosity channel and a lateral extension of hundreds of meters. Even though these four facies associations can be found all over the Punta San Andrés Alloformation, it is possible to identify three different sections (A, B and C, Figs. 9 and 11) in which their arrangement and proportions vary. Each of these sections is associated with specific depositional conditions that determined a characteristic fluvial system. Section A involves the lower and middle allomembers (Fig. 2). It is represented by floodplain deposits (both crevasse-splay and calcic paleosoils associations in a rhythmic arrangement) that are considered to represent a terminal fluvial system. The calcic paleosoils are interpreted to represent a dry and arid climate (Marriott and Wright, 1993; Balin, 2000) under a reduced rate of accommodation creation (Marriott and Wright, 1993; Cleveland et al., 2007). Because of the presence of iron nucleids and clay coatings, the crevasse-splay deposits are interpreted to represent wetter climatic conditions (Davies-Vollum and Kraus, 2001) and developed under a greater rate of accommodation creation (Cleveland et al., 2007). Section B (upper allomember) is also made up of floodplain deposits, although coarser and much more dissected by a larger proportion of complex channels. Hence, they are interpreted as a proximal floodplain. Finally, section C is represented by mobile, highsinuosity channel deposits in such a high proportion that in some parts of the outcrops there is no preservation of floodplain deposits. To summarize, for the Punta San Andrés Alloformation deposits cropping out in Baliza San Andrés and Complejo Turístico Chapadmalal, four facies associations can be proposed based on the facies analysis of the sediments and its geometry. The analysis of these associations allowed defining depositional environments whose interrelation reflected a progressive change in the paleoclimatic and accommodation conditions, probably related to base-level changes. For section A, climate is interpreted to have been dry and arid and related to low accommodation space. During deposition of section B, climate became wetter and accommodation space was increased. Section C is characterized by a lowering in the local base level that led to negative accommodation with fluvial incision. Deposition of channel fills and floodplain deposits indicate the return of positive accommodation space and wet climate.

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Análisis de cadenas de Markov y series de Fourier en una secuencia hemipelágica del Jurásico superior de la Península Antártica

Kietzmann, Diego A.; Cuitiño, José I.; Medina, Rubén A.; Scaso, Roberto A.
2009-07-01

Resumen en español La Formación Ameghino (Kimmeridgiano-Berriasiano), Cuenca Larsen, Península Antártica, está compuesta por una asociación de microfacies de pelitas con radiolarios (P1), pelitas negras (P2), pelitas bioturbadas y peloidales (P3), tobas (T) y areniscas (A) excelentemente preservadas. Este conjunto de microfacies revela sedimentación pelágica/ hemipelágica en un ambiente deficiente en oxígeno, periódicamente interrumpida por caídas de cenizas del arco volcánico a (mas) ntártico. Análisis basados en cadenas de Markov indican la recurrencia de las microfacies y sus relaciones cíclicas. Se interpreta que la alternancia de pelitas con radiolarios y pelitas negras (P1-P2) responde a variaciones en la productividad/dilución, mientras que las microfacies de tobas y areniscas corresponden a depósitos de evento que modificaron las condiciones ambientales y diagenéticas evitando la disolución de los esqueletos de radiolarios en la masa de agua y en el fondo, y generando de este modo una memoria markoviana con ciclos T-P1-P2. Por otra parte, el análisis por transformadas de Fourier indica para los ciclos P1-P2 una duración del orden de 1000 años, en el rango de variaciones sub-Milankovitch. Resumen en inglés The Upper Jurassic strata of the Larsen Basin, in the northeastern tip of the Antarctic Peninsula (Fig. 1), consist of thin, well-bedded, radiolarian-rich shales, fallout tuffs and volcaniclastic sandstones, grouped in a stratigraphic unit known as Ameghino Formation (or Nordenskjöld Formation for British authors - see Whitham and Doyle, 1989). The Ameghino Formation succession records a fine-grained and high-rate continuous suspensive sedimentation in a quiet hemipelagi (mas) c environment, with little reworking at the bottom. A 1.3 m-thick representative section for the Upper Member of the Ameghino Formation was sampled bed by bed and studied under petrographic microscopy for microfacies determination. Cyclicity was defined by means of Markov chain analysis and Fourier series (Blackman- Tukey and wavelet methods). Microfacies: The succession is composed of a microfacies association of radiolarianrich shales (P1), black shales (P2), bioturbated and peloidal shales (P3), tuffs (T) and sandstones (A) superbly preserved (Figs. 2 and 3). Sedimentation took place in an oxygen-depleted environment, periodically interrupted by rapid, event-sedimentation mostly caused by large explosive eruptions at the volcanic arc of the Antarctic Peninsula. The P1 and P2 microfacies are interpreted as the result of the deposition from pelagic suspensions during cycles of varying biological productivity or terrigenous dilution. The microfacies P3 represents similar conditions of sedimentation but higher oxygenation levels at the bottoms. On the other hand, microfacies T and A correspond to fallout deposits and distal turbiditic flows respectively. Microfacies T is associated with siliciclastic explosive volcanic eruptions and microfacies A with reworking of primary pyroclastic deposits. Markov chain and Fourier series analysis: Markov chain analysis reveal cyclic relations between some microfacies with single step transition dependence (Figs. 4 and 5). Transition diagram shows statistically significant transitions from microfacies T and A to P1, between P1 and P2, and also a cycle T-P1-P2 (Fig. 6). Spectra from the Fourier series analysis on 37 pairs P1-P2 (Fig. 7 a) indicate a periodicity of 1140 years (Blackman-Tukey method, 95% confidence, Fig. 7b), and periodicities of 740 and 1160 years (wavelet method, Fig. 7c). Ages were derived from sedimentation rates calculated by Scasso (2001) for the Longing Member due to poor age determinations in the upper Member. A periodicity of about 1000 years may be associated with the Hallstatt cycle of solar activity that influence the intensity of solar radiation reaching the Earth and cause surface temperature variations within the sub-Milankovitch frequency band. A similar frequency was calculated by Scasso (2001) for large volcanic eruptions from the tuff record in the Longing Member. Therefore, P1- P2 transitions are associated to climatic cycles that influence productivity at the surface of the oceans. The accumulation of microfacies T and A are related to events of siliciclastic sedimentation that modified environmental and early-diagenetic conditions avoiding dissolution of radiolarian skeletons in the water body and at the bottom and caused the T and A transitions to P1. P2-T transition might indicate that P2 environmental conditions lasted longer than P1 conditions in spite of the similar thickness observed for both microfacies.

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Antibodies to citrullinated human fibrinogen synthetic peptides in diagnosing rheumatoid arthritis

Pérez Rodríguez, María L.; Gómara, María J.; Ercilla, Guadalupe; Sanmartí, Raimon; Haro Villar, Isabel

12 pages, 9 figures.-- PMID: 17585853 [PubMed].-- Printed version published on Jul 26, 2007.-- Supplementary information (figs. S1-S7, tables S1-S2, 25 pages) available at: http://pubs.acs.org/doi/suppl/10.1021/jm0701932/suppl_file/jm0701932si20070529_011932.pdf | Since aggressive therapy given earl...

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Anti-de Sitter universe dynamics in loop quantum cosmology

Bentivegna, Eloisa; Pawlowski, Tomasz

17 pags. ; 11 figs. ; appendix A-B | A model for a flat isotropic universe with a negative cosmological constant Lambda and a massless scalar field as sole matter content is studied within the framework of loop quantum cosmology. By application of the methods introduced for the model with Lambda=0, ...

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An improved method of constructing binned luminosity functions

Page, M. J.; Carrera, Francisco J.

LaTeX file, 8 pages, uses mn.sty, 5 figs included in text.-- Accepted by MNRAS. | We show that binned differential luminosity functions constructed using the 1/Va method have a significant systematic error for objects close to their parent sample's flux limit(s). This is particularly noticeable when...

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Ambientes de Interacción Eólica-Fluvial en Valles Intermontanos: ejemplos actuales y antiguos/ Fluvial-aeolian interaction deposits in intermontane valleys: modern and ancient examples

Tripaldi, Alfonsina; Limarino, Carlos O
2008-07-01

Resumen en español La interacción entre procesos depositacionales eólicos y fluviales en valles intermontanos de regiones áridas y semiáridas determina geoformas y facies sedimentarias particulares, cuyo reconocimiento en sucesiones antiguas puede resultar clave, no sólo desde el punto de vista paleoambiental sino también paleoclimático. Además, los depósitos de interacción pueden mostrar significativa importancia como rocas reservorios. El análisis del valle del río Guandacol ( (mas) provincia de La Rioja, Argentina) y de tramos específicos de la Formación Vinchina (Sierras Pampeanas Noroccidentales) permitió caracterizar los depósitos de interacción eólica-fluvial tanto en ambientes actuales como en el registro sedimentario. El valle del río Guandacol presenta una planicie entrelazada de canales efímeros asociados a numerosas geoformas eólicas, distinguiéndose dos subambientes: áreas de canal y planicies de intercanal. En las áreas de canal ocurren barras fluviales gravosas, barras y formas de lecho arenosas menores, depósitos arenogravosos de canal propiamente dicho cubiertos parcial o totalmente por láminas de fango; mientras que las geoformas eólicas comprenden parches de arena (por la migración de óndulas de arena y de gránulo), sombras de arena y taludes arenosos. La acción eólica es dominante en las áreas de intercanal, determinando una topografía irregular, de relativamente bajo relieve, por el crecimiento de mantos de óndulas eólicas, formas ancladas a la vegetación (sombras de arena y zibars), protodunas y dunas: barjan y de crestas barjanoides. Se asocian a las geoformas eólicas acumulaciones fluviales formadas durante las crecientes, como mantos de fango y lóbulos de desbordamiento areno-gravosos. Debido al carácter efímero de los cursos fluviales del valle del río Guandacol, puede considerarse que los procesos fluviales y eólicos se encuentran relativamente balanceados lo que resulta en la sobreimposición de depósitos eólicos y fluviales. En tramos del miembro superior de la Formación Vinchina, en facies previamente interpretadas como de fajas de canales meandrosos efímeros, se reconocieron depósitos de interacción eólico-fluviales. Intercalaciones decimétricas en depósitos de canal y de planicie de inundación se identificaron como niveles eólicos. Se caracterizan por la presencia de areniscas finas a muy finas, muy bien seleccionadas y de fábricas depositacionales abiertas, que muestran una delicada laminación, horizontal o entrecruzada de bajo ángulo, con láminas internamente masivas o con gradación inversa de intralámina. El análisis de secciones delgadas muestra como los términos eólicos son mejor seleccionados, presentan muy bajos porcentajes de matriz, y un empaquetamiento más abierto (valores de porosidad de entre 8 y 12%) cuando se los compara con los niveles fluviales. Aunque excepcionalmente citados en el registro geológico, es probable que en ambientes semiáridos los depósitos de interacción eólica-fluvial sean mucho más frecuentes que lo corrientemente asumido. Lo dicho se desprende no sólo de su común presencia en ambientes actuales, sino también del estudio detallado de sucesiones antiguas, como es el caso de la Formación Vinchina. Resumen en inglés Arid to semiarid regions usually show a close interaction between fluvial and aeolian processes resulting in a particular pattern of landforms and sedimentary facies (Langford, 1989; Langford and Chan, 1989). Here we present a characterization of the fluvial-aeolian interaction environment and its distinctive facies, both in modern settings (Guandacol Valley, La Rioja province) and in a sedimentary section of the Vinchina Formation (Northwestern Pampean Ranges). Recogniti (mas) on of these interaction facies in ancient sequences becomes critical not only because of its paleoenvironmental and paleoclimatic significance but also on account of its potential importance as reservoir rocks (Ellis, 1993; Meadows and Beach, 1993). Methodology in Guandacol Valley included mapping of subenvironments by remote sensing and field survey, definition, characterization and sampling of landforms, textural analysis of sediments and description of stratification styles in natural exposures. In the ancient fluvial-aeolian deposits main lithofacies and facies association were identified and described, together with the characterization of sandstones by petrographic studies. Fluvial-aeolian interaction environment in Guandacol Valley (Figs. 1 and 2) is characterized by an ephemeral high-energy gravelly-sandy braidplain associated with abundant aeolian landforms (Tripaldi y Limarino, 1998; Tripaldi, 2002, Tripaldi et al., 2003). This region presents an arid/semiarid regime with average annual precipitations of 130 mm, focus on spring and summer. Two subenvironments have been distinguished in the Guandacol Valley, channel and floodplains (Table 3). The former comprises different kinds of fluvial bars, channel bed deposits and aeolian landforms (Fig. 3). Since most of the year channels remain dry and vegetation cover is scarce, wind action reworked fluvial sediments, determining aeolian rippled mantles and sand shadows (Figs. 4 and 5). According to grain size and morphology two kinds of ripples were recognized in Guandacol Valley: sand aeolian ripples and granule aeolian ripples (Sharp, 1963; Fig. 4). Floodplains are dominated by aeolian landforms (rippled aeolian mantles, sand shadows, zibars, protodunes and dunes; Figs. 6 and 7), with subordinated fluvial deposits (gravelly-sandy overflow mantles and cracked mud drapes; Figs. 6 and 7). Floodplains show an irregular and rolling sandy topography shaped by the emerging of protodunes that evolve to dunes, as well as by the vertical growth of sand shadows and zibars. Although the aeolian sediments could be partially eroded during flood, their importance result from their capacity of producing different types of interactions with fluvial currents. Aeolian bedforms not only can cause temporary dam streams and disruption of the fluvial drainage network (Langford, 1989), but also can supply high quantities of sands promoting rapid saturation of the flooding currents and the consequent amelioration of the flow erosive power. Ancient fluvial-aeolian interaction deposits of the Vinchina Formation (Turner, 1964) are characterized by thin aeolian sandstone bodies interfingered with fluvial rip-up clast conglomerates, sandstones and mudstones deposited in ephemeral meandering plains (Fig. 8). Aeolian levels are 10 to 40-cm thick, tabular to lentiform bodies of well sorted fine to very fine sandstones, showing a very thin parallel or low angle cross-lamination (Fig. 9). Dune deposits were scarcely identified in the studied fluvial-aeolian succession. Remarkable features in the aeolian beds include: 1) inversely graded laminae (product of wind ripple migration), 2) unimodal, symmetrical or positive asymmetric, well to very well sorted sand, 3) open packing and high porosity in sandstones, 4) very low matrix percentage, 5) lack of muddy intraclasts, upper regime structures (as parting lineation) and erosive surfaces, 6) high index ripple forms with coarsest grains at the crest, 7) occurrence of some beds of medium to very coarse (occasionally granule), bimodal sandstones, with parallel to low angle cross-lamination and inversely graded laminae, owing to the development of granule ripples by wind reworking of fluvial sands (Table 4).

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164

A reevaluation of X-irradiation-induced phocomelia and proximodistal limb patterning

Galloway, Jenna L.; Delgado, Irene; Ros, María A.; Tabin, Clifford J.

6 pages, 4 figures.-- PMID: 19553938 [PubMed].-- Article in press. | Supporting information (Suppl. figs. S1-S6) available at: http://www.nature.com/nature/journal/vaop/ncurrent/suppinfo/nature08117.html | Phocomelia is a devastating, rare congenital limb malformation in which the long bones are sho...

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165

A designed protein as experimental model of primordial folding

Sadqi, Mourad; Alba, Eva de; Pérez-Jiménez, Raúl; Sánchez-Ruiz, José M.; Muñoz van den Eynde, Víctor

6 pages, 4 figures.-- Available Open Access at the publisher's site.-- Article in press. | Supporting information (SI Text, Suppl. figs. S1-S2, Suppl. table S1) available at: http://www.pnas.org/content/suppl/2009/02/24/0812108106.DCSupplemental/0812108106SI.pdf | How do proteins accomplish folding ...

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166

A Role for RNAi in the Selective Correction of DNA Methylation Defects

Teixeira, Felipe Karam; Heredia, Fabiana; Sarazin, Alexis; Roudier, François; Boccara, Martine; Ciaudo, Constance

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167

A New Umayyad Palace at the Citadel of Amman

Almagro, Antonio; Olávarri, Emilio
1982-01-01

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168

Fernández Caldas, E.; García, V.; Gutiérrez Jerez, Francisco José; Bravo Rodríguez, J. M.

16 págs, 6 figs, 2 tabs. | The main differences and characteristics among the banana soils are studied in the Canary Islands. Climatic influences on soil characteristics are also given for the different Islands and slops within each Island. pH, CaCO3 and K show the widest variation in correlation wi...

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169

3D-Structure of the interior fusion peptide of HGV/GBV-C by 1H NMR, CD and molecular dynamics studies

Mazzini, S.; Fernández-Vidal, Mònica; Galbusera, V.; Castro-Román, F.; Bellucci, M.C; Ragg, E.; Haro Villar, Isabel

10 pages, 8 figures.-- PMID: 17603997 [PubMed].-- Supplementary information (Figs. S1-S3, tables S1-S2, 3 pages) available at: http://www.sciencedirect.com/science/MiamiMultiMediaURL/B6WB5-4NX2NKW-1/B6WB5-4NX2NKW-1-1/6701/b67d8856b079eefc5f04ac28c2ef05ed/f.doc | Printed version published on Sep 1, 2...

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