1,076 research outputs found
Ordovician and Silurian igneous rocks and orthogeneisses in the Catalonian Coastel Ranges
These rocks exhibit calc-alkaline affinities and may have originated by partial melting of the crust in a post-collision, anorogenic setting. Orthogneisses derived from biotite-bearing leucogranites occur within aprobably cambrian heterogeneous series. Petrological and geochemical features suggest that they might be genetically related to the ordovician vulcanites. Basic sills and volcanoclastic rocks occur intercalated within a mainly pelitic formation in the lower part of the Silurian sequence. The silurian igneous rocks are alkali basalts and may reflect an extensional regime
Ordovician and Silurian igneous rocks and orthogeneisses in the Catalonian Coastel Ranges
These rocks exhibit calc-alkaline affinities and may have originated by partial melting of the crust in a post-collision, anorogenic setting. Orthogneisses derived from biotite-bearing leucogranites occur within aprobably cambrian heterogeneous series. Petrological and geochemical features suggest that they might be genetically related to the ordovician vulcanites. Basic sills and volcanoclastic rocks occur intercalated within a mainly pelitic formation in the lower part of the Silurian sequence. The silurian igneous rocks are alkali basalts and may reflect an extensional regime
The Linares granite (Jaén): cartography, petrology and geochemistry
[Abstract] Magma emplacement within the Linares granite, a part of the Los Pedroches Batholith, took place in the sequence: biotite granodiorite with microgranular enclaves, biotite monzogranites, and dike swarm complexo Dikes are: WNWESE rhyolite to rhyodacite, aplopegmatite and abundant NE-SW ore-bearing quartz. The Linares intrusion and psamo-pelitic Carboniferous host metasediments (Los Pedroches Culm) are, in part, discordantly covered by Mesozoic (Trias) and Tertiary to Quaternary terrigenous deposits. Bulk rock chemistry of granodiorite shows minor variations in Si02 (64.75... 67 wt %) and REE contents (LREE = 158 -160 ppm), and nearly constant Al CNK (ISA) ratio (1.1 - 1.15). Monzogranites have higher Si02 (66.87 - 68.4 wt %), alkali and REE contents (LREE = 168 - 193 ppm), with A/CNK (ISA) ratio of 1.06 - 1.09. Both granodiorite and monzogranites are peraluminous rocks that may correspond to an aluminous association or to evolved terms of an aluminocafemic association (Debon & Lefort, 1983). Variation diagrams for major and trace elements, including REE, of granodiorite and monzogranites are compatible with magmatic differentiation processes by fractional crystallization starting from a primary granodioritic magma
Geochemistry of A Espenuca two-mica granite: origin and evolution
[Abstract] The A Espenuca two-mica granite, situated in the northern sector ofthe Central Iberian Zone, was variably deformed by the Valdoviño Fault. Deformation intensity is observed to increase from W to E, also being more intense in the northern half. Results of the geochemical study of the less deformed granite facies, known in the regionalliterature as the «weakly deformed facies», are presented. Chemical variations are faint (DSi02 z 4%) and reflect a whole composition close to the granite minimum. Analyzed samples correspond to alkali-dch(Na20+K20, x = 8.4 %), CaO-depleted rocks « 0.9 %), showing very low values for the B (=Fe+Mg+Ti) parameter x = 30, and a marked peraluminous
character, A/CNK, x =1.16 (range 1.1-1.26), which from the mineralogical point of view is traduced in the occurrence of muscovite (± garnet). The rocks studied are depleted in REE (LREE =75.77-189.83; x = 117.4), notably in the HREE. They exhibit considerably fractionated pattern (La/Lu)n x = 50 as well as important Eu negative anomalies (Eu/Eu*, x = 0.36). These rocks can be linked by fractionated crystallization processes. Massbalance calculations indicate crystallization ratios < 30%, the fractionated minerals being Kfs, Bt, PI. These values to explain the trace element variations observed in the different samples.
The chemical-mineralogical composition of analyzed facies suggests an origin
by partial melting of crustal rocks (either pelites, schists, meta-greywackes or
orthoderived materials) at considerable depths, where garnet constitutes a restite stable phase. Nevertheless, calculated models show that not aH these materials equally adjust as source to the granite magma. The best fits are obtained considering a source similar to 0110 de Sapo gneisses. Key Words: Two-mica granite, fractional crystallization, partia
The Santa Elena stock (Jaén). An intrusion genetically independent fram the magmatic association of the Los Pedroches Batolith
[Abstract] The Santa Elena stock has been classically considered as belonging to the magmatic association ofthe Los Pedroches Batolith. The stock is intrusive into psammo-pelitic materials Ordovician to Carboniferousin age. The Santa Elena stock is composed of biotite granodiorite to tonalite with gabbro-diorite as enclaves ofvariable size outcropping in northern sectors ofthe
intrusion. Pelitic xenoliths ofvarious sizes, likely related to magma stopping, are common through the massif. The Santa Elena stock is intruded by a dike complex made of aplite and ore-bearing quartz veins. The two main lithological units exhibit different geochemical features with local evidence ofmagmamixing between acid and basic types. The granodioritetonalite
is chemically homogeneous regarding the content of major and trace elements, including REE. These rocks correspond to mildly peraluminous terms ofan alumino-cafemic association ofcalc-alkaline character.The gabbrodiorite enclaves are meta-aluminous and clearly deviate from the geochemical trend defined by granodiorite and tonalite. The rocks from the Santa Elena stock are very different from the common granodiorite types ofthe Los Pedroches Batolith. It appears from the petrological and geochemical data that the Santa Elena stock corresponds to an independent and different magmafrom that at the origin ofthe Los Pedroches to which it had been classically associated
Comparative study of real-time pcr (Taqman probe and sybr green), serological techniques (elisa, ifa and dat) and clinical signs evaluation, for the diagnosis of canine leishmaniasis in experimentally infected dogs
Canine leishmaniasis (CanL) diagnosis is not fully resolved. Currently, two specific methodologies are in continuous development, the detection of the parasite DNA or RNA in target organs and the detection of specific antibodies against Leishmania sp. For a correct diagnosis, it has been shown that the joint use of this type of test is necessary. In this work, a Sybr Green and a TaqMan Probe based on real time PCRs (qPCR) was performed for the detection of Leishmania sp. in order to correlate the results with clinicopathological and serological evaluations (IFA, ELISA and DAT) to propose an optimal biological sample to be used to detect the parasite in both early and late stages of the infection. A total of four samples were processed: conjunctival swabs, popliteal lymph node aspirates, bone marrow aspirates, and peripheral blood from experimentally infected dogs belonging to a larger study. Our results indicated that a single non-invasive sample (conjunctival swab) and the application of both types of qPCR would be reliable for determining Leishmania infection as well as the disease stage in dogs, thus avoiding bone marrow, lymph node aspirate or blood samples collection. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/)
Copper effect on cytochrome b559 of photosystem II under photoinhibitory conditions
The definitive version is available at www.blackwell-synergy.comToxic Cu(II) effect on Cytochrome b559 under aerobic photoinhibitory conditions was examined in two different PSII membrane preparations active in oxygen evolution. The preparations differ in the content of Cytochrome b559 redox potential forms. Difference absorption spectra showed that the presence of Cu(II) induced the oxidation of the high-potential form of Cytochrome b559 in the dark. Addition of hydroquinone reduced the total oxidised high-potential form of Cytochrome b559 present in Cu(II)-treated PSII membranes indicating that no conversion to the low-potential form took place. Spectroscopic determinations of Cytochrome b559 during photoinhibitory treatment showed slower kinetics of Cu(II) effect on Cytochrome b559 as compared to the rapid loss of oxygen evolution activity in the same conditions. This result indicates that Cytochrome b559 is affected after PSII centers are photoinhibited. The high-potential form was more sensitive to toxic Cu(II) action than the low-potential form under illumination at pH 6.0. The content of the high-potential form of Cytochrome b559 was completely lost, however the low-potential content was unaffected in these conditions. This loss did not involve cytochrome protein degradation. Results are discussed in terms of different binding properties of the heme iron to the protonated or unprotonated histidine ligand in the high-potential and low-potential forms of Cytochrome b559, respectively.M. Bernal was recipient of an I3P Programme fellowship from Consejo Superior de Investigaciones Científicas. This work was supported by the Dirección General de Investigación (Grant BMC2002-00031) to R.P. and Gobierno de Aragón (Grant P015/2001) to I.Y., and it has been done within GC DGA 2002 Program of Gobierno de Aragón.Peer reviewe
Calibración de sensores de humedad capacitivos usando redes neuronales
X Jornadas de Investigación de la Zona no Saturada del Suelo, Salamanca (España), 2011El estudio de la variabilidad espacial de la
humedad del suelo a escala de parcela o cuenca agrícola
requiere el uso de redes de sensores de humedad de bajo
coste, que suelen mostrar una fiabilidad limitada y requieren
de calibraciones específicas, especialmente en suelos con
elevados contenidos en arcilla. El presente trabajo pretende
plantear una calibración más fiable de sondas de humedad
mediante un análisis mixto campo-laboratorio. Para la
calibración de campo se dispone de datos gravimétricos;
para la calibración en laboratorio se han usado columnas de
suelo inalterado que tras ser saturadas fueron desecadas en
un entorno controlado mientras se monitorizaba la
evolución de su peso y la de su humedad volumétrica,
medida con diferentes sondas capacitivas Decagon. Tras
obtener curvas de secado y la relación entre la humedad
gravimétrica y la volumétrica es posible realizar una
calibración mejorada específica para cada tipo de suelo. Las
redes neuronales son particularmente útiles para el
modelado de procesos físicos y el ajuste de modelos. En
este trabajo se propone el empleo de dichas herramientas
para obtener calibraciones para las sondas analizadas en el
tipo de suelo objeto de estudio. Los resultados muestran que
dichas calibraciones permiten mejorar la precisión de las
mediciones de humedad realizadas.The study of the spatial variability of soil
water content at agricultural plot or catchment scales
requires the use of low-cost soil water content sensor
networks, which usually show a limited reliability and
require specific calibrations, specially for soils with a high
clay content. This work proposes a more reliable calibration
of soil water content probes with a laboratory analysis.
Minimally disturbed soil columns were saturated with water
and dried in a controlled environment while monitorizing
the evolution of their volumetric soil water content (with
different capacitive Decagon Probes) and weights. After
obtaining the drying curves and the relation between the
volumetric and the measured gravimetric soil water contents
it is possible to achieve an improved calibration specific for
different kinds of soil. Neural networks are especially
interesting for the modeling of physical processes and
model adjustment. In this work, these tools were used in
order to obtain improved calibrations for the analyzed
probes in the studied soil type. Results show that this
calibration improves the accuracy and pMinisterio de Ciencia e Innovación AGL2009 C03-03Junta de Andalucía AGR-478
Energy management of refrigeration systems with thermal energy storage based on non-linear model predictive control
This work addresses the energy management of a combined system consisting of a refrigeration cycle and a thermal energy storage tank based on phase change materials. The storage tank is used as a cold-energy buffer, thus decoupling cooling demand and production, which leads to cost reduction and satisfaction of peak demand that would be infeasible for the original cycle. A layered scheduling and control strategy is proposed, where a non-linear predictive scheduler computes the references of the main powers involved (storage tank charging/discharging powers and direct cooling production), while a low-level controller ensures that the requested powers are actually achieved. A simplified model retaining the dominant dynamics is proposed as the prediction model for the scheduler. Economic, efficiency, and feasibility criteria are considered, seeking operating cost reduction while ensuring demand satisfaction. The performance of the proposed strategy for the system with energy storage is compared in simulation with that of a cycle without energy storage, where the former is shown to satisfy challenging demands while reducing the operating cost by up to 28%. The proposed approach also shows suitable robustness when significant uncertainty in the prediction model is considered
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