Chemistry of the older supracrustals of Archaean age around Sargur

In the Archaeans of the Karnataka craton two stratigraphically distinct volcano-sedimentary sequences occur, namely the older supracrustals of the Sargur type and the younger Dharwar greenstones. The dividing line between these is the 3 by old component of the Peninsular gneiss. The trace and rare earth element chemistry of the Sargur metasediments show, in general, marked similarity to the Archaean sediments. The significant departures are in the nickel and chromium abundances. The REE data of the Sargur pelites of the Terakanambi region represented by Silli-gt-bio-feldspar schists and paragneisses show LREE enrichment and flat to depleted HREE pattern. Banded iron formations have very low REE abundance. They show slightly enriched LREE and flat to depleted HREE pattern. REE abundance in the Mn-horizons is comparable to that of the Archaean sediments. Mn-horizons show enriched LREE and flat HREE with anamolous Eu. REE patterns of these bands is well evolved and has similarities with PAAS

Fuzzy systems and neural networks XML schemas for soft computing

This article presents an XML[2] based language for the specification of objects in the Soft Computing area. The design promotes reuse and takes a compositional approach in which more complex constructs are built from simpler ones; it is also independent of implementation details as the definition of the language only states the expected behaviour of every possible implementation. Here the basic structures for the specification of concepts in the Fuzzy Logic area are described and a simple construct for a generic neural network model is introduced

Multiport Multiband Decoupling Optimization for Miniature Antennas

Multiband multiport antennas are increasingly used for wireless communications and sensing miniature devices. The equations governing the multiport multiband antennas are analyzed in this paper with the objective of drawing the design guidelines for low coupling small antennas. Those guidelines have been applied in the design and optimization of a two-port dual band small antenna of size around λ0/13 x λ0/13 at the lowest frequency. Certain coupling conditions are applied to the port loads achieving a coupling reduction of 8 dB when having a simple two-element real load. A reduction of 27 dB can be obtained when having ideal loads composed by a higher number of elements. The antenna geometry is shown together with coupling minimization results

Screening for coping style increases the power of gene expression studies

Background: Individuals of many vertebrate species show different stress coping styles and these have a striking influence on how gene expression shifts in response to a variety of challenges. Principal Findings: This is clearly illustrated by a study in which common carp displaying behavioural predictors of different coping styles (characterised by a proactive, adrenaline-based or a reactive, cortisol-based response) were subjected to inflammatory challenge and specific gene transcripts measured in individual brains. Proactive and reactive fish differed in baseline gene expression and also showed diametrically opposite responses to the challenge for 80% of the genes investigated. Significance: Incorporating coping style as an explanatory variable can account for some the unexplained variation that is common in gene expression studies, can uncover important effects that would otherwise have passed unnoticed and greatly enhances the interpretive value of gene expression data

Procesos anatécticos (LP-HT) y heterogeneidad litológica en el Complejo Migmatítico de Mindelo (NW Portugal)

The Mindelo Migmatitic Complex crops out in the coastal zone north of Porto (Portugal) and consists of a set of migmatitic and granitic lithologies. Field relationships, petrography, geochemistry and isotopic signature of the various lithologies allow inferring the sequence of anatectic processes that resulted in their characteristic lithological heterogeneity. The metasedimentary sequences (Schist-Greywacke Complex) show chemical composition and isotopic signature identical to the metatexites. Therefore, it is suggested to be the protolith of Mindelo Migmatite Complex lithologies. The melting has occurred in several structural levels and thus at different pressure and temperature conditions, resulting in rocks with specific characteristics. In shallow levels (<3.5 kbar) metatexites are formed essentially by fluid-present partial melting followed by fluid-absent incongruent biotite melting producing peritectic cordierite, quartz, plagioclase and minor amounts of K-feldspar. The melt segregation led to its crystallization in dilatant sites forming masses and veins of leucogranite. In slightly deeper levels the melting rate is higher which leads to the formation of diatexites and two mica granites that intruded metatexites. This material rises in the crust and incorporates abundant xenoliths forming a very heterogeneous granitic body. Tourmalinization of granitoids, migmatite and metasediments occurred at subsolidus conditions associated with aplite-pegmatites that cut all the other lithologies. A last aqueous fluid influx led to muscovitization of metatexites,granitoids and metasediments. The migmatization started after the first ductile deformation phase of Variscan Orogeny (D1) and was continuously active during the following stage of deformation and shear (D3). The several pulses of different fluids that affected the Mindelo Migmatitic Complex probably are related to the emplacement of the syn and late- D3 variscan granites. The Mindelo Migmatite Complex represents an example of migmatites formed in low pressure conditions and illustrates some of the reactions involving melting in high grade pelitic rocks and subsequent mineral alterations due to infiltration of late different fluids.El Complejo Migmatítico de Mindelo aflora en la zona costera de Portugal al norte de Oporto y se compone de un conjunto de litologías migmatíticas y graníticas. Las relaciones de campo, petrografía, geoquímica y las lugar a su típica heterogeneidad litológica. La composición química e isotópica de la secuencia metasedimentaria del Complejo Esquisto-Grauváquico es idéntica a la de las metatexitas, lo que sugiere que sea el protolito de las litologías del Complejo de Mindelo. La fusión se ha producido en varios niveles estructurales y por lo tanto en diferentes condiciones de presión y temperatura, dando lugar a rocas con características específicas: i) en niveles relativamente superficiales (<3,5 kbar), las metatexitas se forman principalmente por fusión parcial húmeda seguida de fusión incongruente de biotita produciendo cordierita peritéctica, cuarzo, plagioclasa y cantidades menores de feldespato potásico. Los leucogranitos y venas de leucogranito son consecuencia de la migración de leucosomas. En niveles ligeramente más profundas la tasa de fusión es superior, lo que conduce a la formación de diatexitas y de granitos de dos micas que intruyen a las metatexitas. Este material se eleva en la corteza e incorpora abundantes xenolitas formando un cuerpo granítico muy heterogéneo. La turmalinización de leucogranitos, granitos de dos micas, migmatitas y metasedimentos tuvo lugar en condiciones subsolidus, asociada a aplitas/pegmatitas que cortan al resto de litologías. Una última entrada de fluidos acuosos condujo a la moscovitización de metatexitas, granitoides y metasedimentos. La migmatización comenzó después de la fase de engrosamiento cortical de la Orogenia Varisca y estuvo activa durante la siguiente etapa de deformación y cizalla. Los pulsos de diferentes fluidos que afectaron el Complejo Migmatítico de Mindelo probablemente están relacionados con el emplazamiento de los cuerpos graníticos sin y tardi -D3. El Complejo Migmatítico de Mindelo representa un ejemplo de migmatitas formadas en condiciones de baja presión e ilustra algunas de las reacciones que implican la fusión de rocas pelíticas en alto grado y sus alteraciones minerales posteriores debido a la infiltración de diferentes tipos de fluidos

A procedure for indirect and automatic measurement of prior austenite grain size in bainite/martensite microstructures

An alternative procedure for indirect and automatic measurement of the prior austenite grain size (PAGS) in bainite/martensite is proposed in this work. It consists in the determination of an effective grain size (EGS) by means of statistical post-processing of electron backscatter diffraction (EBSD) data. The algorithm developed for that purpose, which is available on-line, has been applied to simulated EBSD maps as well as to both a nanocrystalline bainitic steel and a commercial hot-rolled air-cooled steel with a granular bainitic microstructure. The new proposed method has been proven to be robust and results are in good agreement with conventional PAGS measurements. The added value of the procedure comes from its simplicity, as no parent reconstruction is involved during the process, and its suitability for low-magnification EBSD maps, thus allowing a large step-size and coverage of a substantially broader area of the sample than the previous methods reported.Spanish Ministry of Economy and Competitiveness for funding this research under the contract IPT-2012-0320-420000. L.M.-R. also acknowledges the Spanish Ministry of Economy and Competitiveness for financial support in the form of a PhD research grant (FPI-Ref. BES-2011-044186).Peer reviewe

Giochi da senatori

Megalencephalic leucoencephalopathy with subcortical cysts is a genetic brain disorder with onset in early childhood. Affected infants develop macrocephaly within the first year of life, after several years followed by slowly progressive, incapacitating cerebellar ataxia and spasticity. From early on, magnetic resonance imaging shows diffuse signal abnormality and swelling of the cerebral white matter, with evidence of highly increased white matter water content. In most patients, the disease is caused by mutations in the gene MLC1, which encodes a plasma membrane protein almost exclusively expressed in brain and at lower levels in leucocytes. Within the brain, MLC1 is mainly located in astrocyte-astrocyte junctions adjacent to the blood-brain and cereborspinal fluid-brain barriers. Thus far, the function of MLC1 has remained unknown. We tested the hypothesis that MLC1 mutations cause a defect in ion currents involved in water and ion homeostasis, resulting in cerebral white matter oedema. Using whole-cell patch clamp studies we demonstrated an association between MLC1 expression and anion channel activity in different cell types, most importantly astrocytes. The currents were absent in chloride-free medium and in cells with disease-causing MLC1 mutations. MLC1-dependent currents were greatly enhanced by hypotonic pretreatment causing cell swelling, while ion channel blockers, including Tamoxifen, abolished the currents. Down regulation of endogenous MLC1 expression in astrocytes by small interfering RNA greatly reduced the activity of this channel, which was rescued by overexpression of normal MLC1. The current-voltage relationship and the pharmacological profiles of the currents indicated that the channel activated by MLC1 expression is a volume-regulated anion channel. Such channels are involved in regulatory volume decrease. We showed that regulatory volume decrease was hampered in lymphoblasts from patients with megalencephalic leucoencephalopathy. A similar trend was observed in astrocytes with decreased MLC1 expression; this effect was rescued by overexpression of normal MLC1. In the present study, we show that absence or mutations of the MLC1 protein negatively impact both volume-regulated anion channel activity and regulatory volume decrease, indicating that megalencephalic leucoencephalopathy is caused by a disturbance of cell volume regulation mediated by chloride transport. © 2011 The Author