CTCF orchestrates the germinal centre transcriptional program and prevents premature plasma cell differentiation

In germinal centres (GC) mature B cells undergo intense proliferation and immunoglobulin gene modification before they differentiate into memory B cells or long-lived plasma cells (PC). GC B-cell-to-PC transition involves a major transcriptional switch that promotes a halt in cell proliferation and the production of secreted immunoglobulins. Here we show that the CCCTC-binding factor (CTCF) is required for the GC reaction in vivo, whereas in vitro the requirement for CTCF is not universal and instead depends on the pathways used for B-cell activation. CTCF maintains the GC transcriptional programme, allows a high proliferation rate, and represses the expression of Blimp-1, the master regulator of PC differentiation. Restoration of Blimp-1 levels partially rescues the proliferation defect of CTCF-deficient B cells. Thus, our data reveal an essential function of CTCF in maintaining the GC transcriptional programme and preventing premature PC differentiation

El gas somero en los sedimentos de la Ría de Muros-Noia (NO de España): formas de aparición y cartografía

High-resolution seismic reflection and side-scan sonar records have been analysed and interpreted in order to detect shallow gas signatures in the Ría de Muros-Noia (NW Spain). The different gas features have been classified into four types according to their specific seismic signatures: 1) acoustic blankings s.s., with a flat top surface and kilometric extent, 2) acoustic curtains, with a convex top surface and some tens of meters of lateral extent, 3) acoustic columns, with an enhanced reflector at the top and an averaged extent of 20 m, and 4) acoustic turbidity, distinguishable as a diffuse perturbation of the records. At the same time, two different types of gas escape features have been also distinguished: a) acoustic plumes into the water column, rising up to 10 m above the present seafloor, and b) pockmarks on the present seabed, recognised as highly reflective areas in the side-scan sonar records. Mapping of acoustic blankings s.s. reveals the presence of a large gas field (11.5 km2) in the inner part of the ría. In this field the top of the gas accumulates from the close seabed surface up to 4 ms TWT (3.2 m) in depth. Moreover a map with the spatial distribution of the gas accumulations and of the gas escape features is shown

Prismas trasescalares en el estudio de las migraciones

This article aims to reflect on the way social anthropology can contribute to the study of migrations and, simultaneously, to “find out” what the discipline can also learn from this field of study, and thus to transfer its knowledge to other areas. From here we will learn how important here and there are for the study of migrations, not as situations or places, but as constructed and reconstructed notions of identification processes. From that point, we will try to show some examples of our ethnographic research that lead to the analysis of the concept of situation from its relational dimension. A notion of context that shouldn’t be seen in relation to space, but in the provision of meanings for the social and cultural events within it. Therefore a trans-scalar approach of anthropology will arise in a global context and referring to any sociocultural pnenomenon. Such an approach wil lead to the enforcement of a multisited ethnography.El presente artículo pretende reflexionar sobre lo que la antropología social puede aportar al estudio de las migraciones y, a la vez, “descubrir” lo que puede aprender también la disciplina de este campo de estudio, y, de esta manera transdisciplinar, sus saberes. De aquí aprenderemos lo importante que es para el estudio de las migraciones el aquí y allí no como situaciones o lugares, sino como nociones que construyen y reconstruyen los procesos de identificación. Desde ellos trataremos de mostrar varios ejemplos de nuestras investigaciones etnográficas, que nos pongan en la situación de analizar el concepto de contexto desde sus dimensiones relacionales. Es una noción de contexto que no debe dimensionarse en lo espacial, sino en la dotación de significados de los acontecimientos sociales y culturales que deben ser inscritos en él. De todo ello surgirá el enfoque transescalar, que en un contexto global debe tomar la antropología en el estudio de cualquier fenómeno sociocultural, lo que le obligará a intensificar una etnografía multisituada

Long-term quality assurance of fMRI and MRS on a 3.0T clinical scanner

Functional MRI (fMRI) and Magnetic Resonance Spectroscopy (MRS) are being increasingly used in clinical protocols. Subsequenly it is crucial to develop a routine quality assurance protocol (QA)of both techniques. This work describes a long-term variability study, as apart of the QA of fMRI and MRS on our institution clinical 3.0 T MR scanner

Development of indices of larval bluefin tuna (Thunnus thynnus) in the western Mediterranean sea

Fishery independent indices of bluefin tuna larvae in the western Mediterranean Sea are presented utilizing ichthyoplankton survey data collected from 2001 through 2005 by the Spanish Institute of Oceanography. Indices were developed using larval catch rates collected using two different types of bongo gear by employing a delta-lognormal modeling approach, including following covariates: water temperature at 25 m, salinity at 25 m, water depth, time of day, geostrophic water velocities, year, and a gear variable for the combined modelSe presentan índices de larvas de atún rojo independientes de la pesquería en el mar Mediterráneo occidental utilizando datos de prospecciones de ictioplancton recopilados desde 2001 hasta 2005 por el Instituto Español de Oceanografía. Los índices se desarrollaron utilizando tasas de captura larval recopiladas utilizando dos tipos diferentes de red bongo y empleando un enfoque delta-lognormal de modelación, que incluía las siguientes covariables: temperatura del agua a 25 m, salinidad a 25 m, profundidad del agua, hora del día, velocidad del agua geostrófica, año y una variable de arte para el modelo combinad

qq-Classical orthogonal polynomials: A general difference calculus approach

It is well known that the classical families of orthogonal polynomials are characterized as eigenfunctions of a second order linear differential/difference operator. In this paper we present a study of classical orthogonal polynomials in a more general context by using the differential (or difference) calculus and Operator Theory. In such a way we obtain a unified representation of them. Furthermore, some well known results related to the Rodrigues operator are deduced. A more general characterization Theorem that the one given in [1] and [2] for the q-polynomials of the q-Askey and Hahn Tableaux, respectively, is established. Finally, the families of Askey-Wilson polynomials, q-Racah polynomials, Al-Salam & Carlitz I and II, and q-Meixner are considered. [1] R. Alvarez-Nodarse. On characterization of classical polynomials. J. Comput. Appl. Math., 196:320{337, 2006. [2] M. Alfaro and R. Alvarez-Nodarse. A characterization of the classical orthogonal discrete and q-polynomials. J. Comput. Appl. Math., 2006. In press.Comment: 18 page

Spatial and temporal analysis of the seasonal and interannual variability in the tropical Pacific simulated with a coupled GCM

In the first part of this work, the dominant time scales that explain the tropical variability of the first SINTEX simulation (ECHAM4(T30)-ORCA) are identified through a spectral analysis. Higher order spectral analysis is used to examine the interactions among these time scales. The time series analyzed are an average of sea surface temperature over the Niño3 region. The time scales obtained are compared with those identified in another coupled GCM simulation (ECHAM4(T42)-OPYC3). The higher importance of the biannual time scale in this last is explained partly by the strength of the coupling between the annual and the biannual time scales. There is no such strong coupling in the SINTEX simulation. Important differences among the generation of the simulated warm (or cold) event suggest the need of a systematic classification to isolate their relevant features. Therefore in the second part of this work, we address this problem. A space-time cluster analysis is performed on a data set built by collecting the values of the heat content anomalies in the tropical Pacific region, in the fifteen months previous to a peak in the Niño3 Index that has been identified as a ‘warm’ (or ‘cold’) event. In the case of the warm events, three types of generation schemes are found. In two of them, there are anomalies of heat content in the west, north and south of the equator, more than nine months before the events start. In the third case, the anomalies appear and grow in the central equatorial Pacific. Only two types are needed to classify the generation of cold events. Negative sea level height anomalies appear six months before the Niño3 Index reaches the (local) minimum. They are located north of the equator in one of the groups, and south of it in the other. Some of these characteristic traits also appear in observations of warm and cold events

Algunas soluciones exactas para una ecuación de Klein Gordon

In solving practical problems in science and engineering arises as a direct consequence differential equations that explains the dynamics of the phenomena. Finding exact solutions to this equations provides importan information about the behavior of physical systems. The Lie symmetry method allows tofind invariant solutions under certain groups of transformations for differential equations.This method not very well known and used is of great importance in the scientific community. By this approach it was possible to find several exactinvariant solutions for the Klein Gordon Equation uxx − utt = k(u). A particularcase, The Kolmogorov equation uxx − utt = k1u + k2un was considered.These equations appear in the study of relativistic and quantum physics. The general solutions found, could be used for future explorations on the study for other specific K(u) functions.Al resolver problemas prácticos en ciencia e ingeniería surge como consecuencia directa las ecuaciones diferenciales que explican la dinámica de los fenómenos. Encontrar soluciones exactas a estas ecuaciones proporciona información importante sobre el comportamiento de los sistemas físicos. El método de simetría de Lie permite encontrar soluciones invariantes bajo ciertos grupos de transformaciones para ecuaciones diferenciales. Este método, poco conocido y utilizado, es de gran importancia en la comunidad científica. Mediante este enfoque, fue posible encontrar varias soluciones exactas invariables para la ecuación de Klein Gordon uxx - utt = k (u). Un caso particular, se consideró la ecuación de Kolmogorov uxx - utt = k1u + k2un. Estas ecuaciones aparecen en el estudio de la física relativista y cuántica. Las soluciones generales encontradas podrían utilizarse para futuras exploraciones en el estudio para otras funciones específicas de K (u)

Herbaceous biomass estimation using hyperspectral data, PLS regression and continuum removal transformation

Revista oficial de la Asociación Española de Teledetección[EN] The aim of this research work was to compare the results of two methods to estimate aboveground biomass by using field spectrometer data: (i) Partial least squares regression (PLSR), and (ii) linear regression applied to the Maximum Band Depth (MBD) and Area Over the Minimum (AOM) indices. In both cases different regions of the spectrum were transformed by Continuum Removal (CR). Since the results using PLSR (R2=0.920, RMSE=3.622 g/m2) were similar to the results achieved by the indices (R2=0.915, RMSE=3.615 g/m2 for AOM), using the indices derived from CR is recommended, since their interpretation is easier than the PLS output.[ES] El objetivo del estudio fue comparar los resultados de dos métodos para la estimación de la biomasa aérea a partir de datos de espectroradiometría de campo: (i) regresión por mínimos cuadrados parciales (Partial Least Squa-res Regression, PLSR) y (ii) regresión lineal utilizando los índices Profundidad del Mínimo (Maximum Band Depth, MBD) y Área Sobre el Mínimo (Area Over the Minimum, AOM) como descriptores. En ambos casos se llevó a cabo una previa transformación de los espectros mediante Continuum Removal (CR). Como los resultados empleando PLS (R2=0,920, RMSE=3,622 g/m2) fueron muy similares a los obtenidos con los índices (para AOM: R2=0,915, RMSE=3,615 g/m2), recomendamos los índices derivados del CR puesto que su interpretación es más sencilla que la del PLSRMarabel-García, M.; Álvarez-Taboada, F. (2014). Estimación de biomasa en herbáceas a partir de datos hiperespectrales, regresión PLS y la transformación continuum removal. Revista de Teledetección. (42):49-60. https://doi.org/10.4995/raet.2014.228649604

Las zonas arqueológicas como paisajes culturales: el parque arqueológico de Las Médulas(León)

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