Contribución de la mineralogía de arcillas a la interpretación de la evolución paleogeografica del sector occidental de la Cuenca del Guadalquivir

Marine tertiary materials of the Guadalquivir basin consist of four mayor depositional sequences of great continuity in the whole basin which are separate by unconformities. The lower outcroping unit (unit 2) ineludes glauconite-rich sandstones and marly limestones (Fm. Calcarenitas de Niebla, Tortonian-Messinian) and Olisthostromic materials. This unit lies discordantly over the Paleozoic, and was sedimented in a shaUow marine platform. Olisthostromic materials (Mesozoic and Miocene), composed of sand and elayey sand, were deposited during Tortonian-Messinian times. As a consequence of a transgressive pulse, the sedimentation of a thick marly series (Fm. Arcillas de Gibraleón) ofthe Messinian-Low Pliocene age took place. In the last stages of the filling of the basin (Pliocene) a regression began, and sands and silts were deposited (Fm. Arenas de Huelva and Fm. Arenas de Bonares). Also, and as a final consequence of the regression stage, lacustrine sedimentary deposits (Upper Pliocene) occur at the south of the basin, which are composed of marly limestone and greenish palygorskite and sepiolite marls. From a mineralogical point of view, autochthonous materials from this marine detritalcarbonate series, are mainly composed of calcite, quartz and phyUosilicates with minor dolomite and feldspars, and secondary gypsum. The elay minerals present are illite and smectite with minor kaolinite and chlorite. The evolution of the elay minerals associations varies from bottom to top as foUows: Illite or Clauconite >> Smectite > Chlorite/Kaolinite (Fm. Calcarenitas de Niebla); Smectite ≥ Illite > Kaolinite (Lower Fm. Arcillas de Gibraleón); Illite > Smectite ≥ Kaolinite/Chlorite) (Upper Fm. Arcillas de Gibraleón), and Smectite > Illite > Kaolinite (Fm. Arenas de Huelva y Fm. Arenas de Bonares). This vertical variation confirms a stratigraphical discontinuity (paraconformity) into the Fm. Arcillas de Gibraleón, which was observed by others from stratigraphical and paleontological data, and supports a new mineralogical change between the Fm. Arcillas de Gibraleón y Fm. Arenas de Huelva. Sedimentation of those materials above described took place in a shallow marine environment which was more superficial upward, according to palaeontological data. The illite crystal-chemistry characteristics, suggest that metamorphic and igneous rocks from the South Iberian Massif should be the source area for these sediments. The mineralogical composition of allochthonous materials are quartz, opal-A and opalCT, phyllosilicates, and calcite. The clayminerals are predominantly smectites and minor amounts of illite and kaolinite. The microfauna associations together with the absence of detrital minerals, may support that sedimentation of these materials took place in a rather shallow marine basin (< 150 m deepth). The presence of opal A and CT, seem to indicate that sediments have only undergone an early diagenesis. The source area for these materials could be the Triassic materials of the Betic Cordillera.Los minerales de la arcilla presentes en los materiales terciarios del SO de la Cuenca del Guadalquivir son illita, esmectitas, con elorita y caolinita en menores proporciones. El estudio de la variación vertical y lateral de las asociaciones mineralógicas ha permitido aportar datos que complementan los ya existentes de tipo estratigráfico o paleontológico. En concreto se han correlacionado espacialmente los distintos materiales, y se confirma por mineralogía de arcillas la ruptura sedimentaria propuesta por otros autores dentro de la Formación Arcillas de Gibraleón, también se observa un cambio mineralógico no detectado anteriormente en el paso de la Formación ArciUas de Gibraleón a la Serie de Transición o la Formación Arenas de Huelva. Se da una interpretación sobre el medio y condiciones de depósito para los materiales autóctonos y parautóctonos y se propone como área fuente de estos materiales las pizarras alumínicas y ferromagnesianas del Macizo Ibérico y los materiales triásicos de la Cordillera Bética. Por último, se propone un modelo de evolución paleogeográfica de la cuenca

Novel types of anti-ecloud surfaces

In high power RF devices for space, secondary electron emission appears as the main parameter governing the multipactor effect and as well as the e-cloud in large accelerators. Critical experimental activities included development of coatings with low secondary electron emission yield (SEY) for steel (large accelerators) and aluminium (space applications). Coatings with surface roughness of high aspect ratio producing the so-call secondary emission suppression effect appear as the selected strategy. In this work a detailed study of the SEY of these technological coatings and also the experimental deposition methods (PVD and electrochemical) are presented. The coating-design approach selected for new low SEY coatings include rough metals (Ag, Au, Al), rough alloys (NEG), particulated and magnetized surfaces, and also graphene like coatings. It was found that surface roughness also mitigate the SEY deterioration due to aging processes.Comment: 4 pages, contribution to the Joint INFN-CERN-EuCARD-AccNet Workshop on Electron-Cloud Effects: ECLOUD'12; 5-9 Jun 2012, La Biodola, Isola d'Elba, Italy; CERN Yellow Report CERN-2013-002, pp.153-15

Funcionalidad familiar y estilos de vida saludable en pacientes con linfoma Hodgkin en Bogotá

Se realizó una investigación cuantitativa descriptiva y transversal en un grupo de pacientes con linfoma Hodgkin para determinar la relación entre funcionalidad familiar y los estilos de vida saludable. Se usaron los instrumentos Escala de Evaluación de la Funcionalidad Familiar y el Health Promoting Lifestyle Profile II, los dos en su versión en español. El informante familiar fue el paciente con diagnóstico de linfoma Hodgkin. Se encontró predominio de un nivel bajo de funcionalidad familiar y frecuencia de estilos de vida saludable A veces y Frecuentemente; se determinó que solo hubo correlación con significancia estadística entre la dimensión Relaciones interpersonales, perteneciente a los estilos de vida saludable, y la funcionalidad familiar. Se requiere profundizar en esta temática con otros grupos de pacientes para lograr un mejor conocimiento al respecto

The status of chestnut cultivation and utilization in the Canary Islands

Chestnut was introduced to the Canary Islands at the beginning of the 16th century during the time of the Spanish Conquest. It was utilised by the conquerors as a means of claiming property for communal lands. From that time until today, chestnut has been an important crop in the Canary Islands. It is important both as a source of food and timber and has contributed to the subsistence of the population, particularly at times when both resources were scarce. Nowadays it is mainly cultivated on the Islands of Tenerife (around 1300 ha) and La Palma. On other islands, such as Gran Canaria, La Gomera and El Hierro, semi-wild chestnut forests and small plots where farmers collect fruit still exist. Morphological and molecular marker (SSRs) studies have shown a great variability within the local population of chestnut trees in the Canaries. The main use for chestnut is fruit consumption, but it was also utilised in the past as an exchange commodity to obtain fish and other food. The fruit is consumed in many different ways, mainly toasted or roasted, but also cooked in soups, fish or meat dishes and even as an ingredient for the typical Canary Islands’ sweet ‘morcillas’ (a type of sausage). The wood of the tree has been used for furniture, with some shoots being utilised for basket making, and also as cattle food. The trunk of the chestnut has also been used to obtain cork or as a bee hive. Recent efforts to add value to chestnut cultivation in the Canary Islands have included the creation of a Chestnut Farmers Association in Tenerife that commercializes their products under a brand name

Chemoselective and stereoselective lithium carbenoid mediated cyclopropanation of acyclic allylic alcohols

The reaction of geraniol with different lithium carbenoids generated from n-BuLi and the corresponding dihaloalkane has been evaluated. The reaction occurs in a chemo and stereoselective manner, which is consistent with a directing effect from the oxygen of the allylic moiety. Furthermore, a set of polyenes containing allylic hydroxyl or ether groups were chemoselectively and stereoselectively converted into the corresponding gem-dimethylcyclopropanes in one single step in moderate to good yields mediated by a lithium carbenoid generated in situ by the reaction of n-BuLi and 2,2-dibromopropane

Graphene oxide: key to efficient charge extraction and suppression of polaronic transport in hybrids with poly (3-hexylthiophene) nanoparticles

Nanoparticles (NPs) of conjugated polymers in intimate contact with sheets of graphene oxide (GO) constitute a promising class of water-dispersible nanohybrid materials of increased interest for the design of sustainable and improved optoelectronic thin-film devices, revealing properties exclusively pre-established upon their liquid-phase synthesis. In this context, we report for the first time the preparation of a P3HTNPs–GO nanohybrid employing a miniemulsion synthesis approach, whereby GO sheets dispersed in the aqueous phase serve as a surfactant. We show that this process uniquely favors a quinoid-like conformation of the P3HT chains of the resulting NPs well located onto individual GO sheets. The accompanied change in the electronic behavior of these P3HTNPs, consistently confirmed by the photoluminescence and Raman response of the hybrid in the liquid and solid states, respectively, as well as by the properties of the surface potential of isolated individual P3HTNPs–GO nano-objects, facilitates unprecedented charge transfer interactions between the two constituents. While the electrochemical performance of nanohybrid films is featured by fast charge transfer processes, compared to those taking place in pure P3HTNPs films, the loss of electrochromic effects in P3HTNPs–GO films additionally indicates the unusual suppression of polaronic charge transport processes typically encountered in P3HT. Thus, the established interface interactions in the P3HTNPs–GO hybrid enable a direct and highly efficient charge extraction channel via GO sheets. These findings are of relevance for the sustainable design of novel high-performance optoelectronic device structures based on water-dispersible conjugated polymer nanoparticles

X-ray detection with Micromegas with background levels below 10−6^{-6} keV−1^{-1}cm−2^{-2}s−1^{-1}

Micromegas detectors are an optimum technological choice for the detection of low energy x-rays. The low background techniques applied to these detectors yielded remarkable background reductions over the years, being the CAST experiment beneficiary of these developments. In this document we report on the latest upgrades towards further background reductions and better understanding of the detectors' response. The upgrades encompass the readout electronics, a new detector design and the implementation of a more efficient cosmic muon veto system. Background levels below 10$^{-6}$keV$^{-1}$cm$^{-2}$s$^{-1}$ have been obtained at sea level for the first time, demonstrating the feasibility of the expectations posed by IAXO, the next generation axion helioscope. Some results obtained with a set of measurements conducted in the x-ray beam of the CAST Detector Laboratory will be also presented and discussed