The C-terminal domain of the largest subunit of RNA polymerase II interacts with a novel set of serine/arginine-rich proteins.

Although transcription and pre-mRNA processing are colocalized in eukaryotic nuclei, molecules linking these processes have not previously been described. We have identified four novel rat proteins by their ability to interact with the repetitive C-terminal domain (CTD) of RNA polymerase II in a yeast two-hybrid assay. A yeast homolog of one of the rat proteins has also been shown to interact with the CTD. These CTD-binding proteins are all similar to the SR (serine/arginine-rich) family of proteins that have been shown to be involved in constitutive and regulated splicing. In addition to alternating Ser-Arg domains, these proteins each contain discrete N-terminal or C-terminal CTD-binding domains. We have identified SR-related proteins in a complex that can be immunoprecipitated from nuclear extracts with antibodies directed against RNA polymerase II. In addition, in vitro splicing is inhibited either by an antibody directed against the CTD or by wild-type but not mutant CTD peptides. Thus, these results suggest that the CTD and a set of CTD-binding proteins may act to physically and functionally link transcription and pre-mRNA processing.

Membrane lipid perturbation modifies the set point of the temperature of heat shock response in yeast.

Addition of a saturated fatty acid (SFA) induced a strong increase in heat shock (HS) mRNA transcription when cells were heat-shocked at 37 degrees C, whereas treatment with an unsaturated fatty acid (UFA) reduced or eliminated the level of HS gene transcription at 37 degrees C. Transcription of the delta 9-desaturase gene (Ole1) of Histoplasma capsulatum, whose gene product is responsible for the synthesis of UFA, is up-regulated in a temperature-sensitive strain. We show that when the L8-14C mutant of Saccharomyces cerevisiae, which has a disrupted Ole1 gene, is complemented with its own Ole1 coding region under control of its own promoter or Ole1 promoters of H. capsulatum, the level of HS gene transcription depends on the activity of the promoters. Fluorescence anisotropy of mitochondrial membranes of completed strains corresponded to the different activity of the Ole1 promoter used. We propose that the SFA/UFA ratio and perturbation of membrane lipoprotein complexes are involved in the perception of rapid temperature changes and under HS conditions disturbance of the preexisting membrane physical state causes transduction of a signal that induces transcription of HS genes.

POU domain factor Brn-3b is required for the development of a large set of retinal ganglion cells.

The three members of the Brn-3 family of POU domain transcription factors are found in highly restricted sets of central nervous system neurons. Within the retina, these factors are present only within subsets of ganglion cells. We show here that in the developing mouse retina, Brn-3b protein is first observed in presumptive ganglion cell precursors as they begin to migrate from the zone of dividing neuroblasts to the future ganglion cell layer, and that targeted disruption of the Brn-3b gene leads in the homozygous state to a selective loss of 70% of retinal ganglion cells. In Brn-3b (-/-) mice other neurons within the retina and brain are minimally or not at all affected. These experiments indicate that Brn-3b plays an essential role in the development of specific ganglion cell types.

A set of genes expressed in response to light in the adult cerebral cortex and regulated during development.

Activity-dependent plasticity is thought to underlie both formation of appropriate synaptic connections during development and reorganization of adult cortical topography. We have recently cloned many candidate plasticity-related genes (CPGs) induced by glutamate-receptor activation in the hippocampus. Screening the CPG pool for genes that may contribute to neocortical plasticity resulted in the identification of six genes that are induced in adult visual cortical areas in response to light. These genes are also naturally induced during postnatal cortical development. CPG induction by visual stimulation occurs primarily in neurons located in cortical layers II-III and VI and persists for at least 48 hr. Four of the visually responsive CPGs (cpg2, cpg15, cpg22, cpg29) are previously unreported genes, one of which (cpg2) predicts a "mini-dystrophin-like" structural protein. These results lend molecular genetic support to physiological and anatomical studies showing activity-dependent structural reorganization in adult cortex. In addition, these results provide candidate genes the function of which may underlie mechanisms of adult cortical reorganization.

A fast marching level set method for monotonically advancing fronts.

A fast marching level set method is presented for monotonically advancing fronts, which leads to an extremely fast scheme for solving the Eikonal equation. Level set methods are numerical techniques for computing the position of propagating fronts. They rely on an initial value partial differential equation for a propagating level set function and use techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. This paper describes a particular case of such methods for interfaces whose speed depends only on local position. The technique works by coupling work on entropy conditions for interface motion, the theory of viscosity solutions for Hamilton-Jacobi equations, and fast adaptive narrow band level set methods. The technique is applicable to a variety of problems, including shape-from-shading problems, lithographic development calculations in microchip manufacturing, and arrival time problems in control theory.

Image processing via level set curvature flow.

We present a controlled image smoothing and enhancement method based on a curvature flow interpretation of the geometric heat equation. Compared to existing techniques, the model has several distinct advantages. (i) It contains just one enhancement parameter. (ii) The scheme naturally inherits a stopping criterion from the image; continued application of the scheme produces no further change. (iii) The method is one of the fastest possible schemes based on a curvature-controlled approach.

Replication factor encoded by a putative oncogene, set, associated with myeloid leukemogenesis.

DNA replication of the adenovirus genome complexed with viral core proteins is dependent on the host factor designated template activating factor I (TAF-I) in addition to factors required for replication of the naked genome. Recently, we have purified TAF-I as 39- and 41-kDa polypeptides from HeLa cells. Here we describe the cloning of two human cDNAs encoding TAF-I. Nucleotide sequence analysis revealed that the 39-kDa polypeptide corresponds to the protein encoded by the set gene, which is the part of the putative oncogene associated with acute undifferentiated leukemia when translocated to the can gene. The 41-kDa protein contains the same amino acid sequence as the 39-kDa protein except that short N-terminal regions differ in both proteins. Recombinant proteins, which were purified from extracts of Escherichia coli, expressing the proteins from cloned cDNAs, possessed TAF-I activities in the in vitro replication assay. A particular feature of TAF-I proteins is the presence of a long acidic tail in the C-terminal region, which is thought to be an essential part of the SET-CAN fusion protein. Studies with mutant TAF-I proteins devoid of this acidic region indicated that the acidic region is essential for TAF-I activity.

Invariance and restriction toward a limited set of self-antigens characterize neonatal IgM antibody repertoires and prevail in autoreactive repertoires of healthy adults.

Analysis of the reactivity of IgM with self-antigens in tissues by a quantitative immunoblotting technique showed striking invariance among newborns in the human and in the mouse. The self-reactive repertoire of IgM of adults was also markedly conserved; it comprised most anti-self reactivities that prevailed among neonates. Multivariate analysis confirmed the homogeneity of IgM repertoires of neonates toward self- and non-self-antigens. Multivariate analysis discriminated between newborn and adult repertoires for reactivity with two of five sources of self-proteins and with non-self-antigens. Our observations support the concept that naturally activated B lymphocytes are selected early in development and throughout life for reactivity with a restricted set of self-antigens.

Los agentes informativos en los telediarios españoles. Resultados de Quién Habla y De Quién se Habla del otoño de 2013 al otoño de 2015 (13S2-15S)

El presente documento recoge los resultados (data set) de la investigación realizada por el Observatorio de la Calidad de la Información en Televisión (OCITV) sobre los telediarios españoles entre el 2º semestre de 2013 y el 1º de 2015, en concreto sobre dos grupos de variables (Quién Habla y De Quién se Habla) que muestra la representación de los agentes informativos. Estos datos han sido la base para el siguiente trabajo: Aparicio González, Daniel; Salgado Santamaría, Carmen; Díaz Arias, Rafael (2016): “Telediarios: reforzamiento del status quo, cambio sociopolítico y espectáculo. El análisis del OCITV”. Congreso AE_IC. Madrid, julio 2016. OCITV es un grupo de investigación UCM, compuesto por Rafael Díaz Arias (coordinador), Carmen Salgado Santamaría, Daniel Aparicio González, Joaquín Sotelo González, Julia González Conde, Roberto Gamonal Arroyo, Paloma Hidalgo Goyanes y José Luis Gallardo Bueno. El OCITV ya ha publicado un artículo sobre metodología (Díaz Arias, R.; González Conde, J; Aparicio González, D. (2015): “Parámetros de calidad en la información de televisión. La metodología del observatorio de la calidad de la información en televisión”. Ámbitos nº 30). Otros trabajos versarán sobre la temática de los telediarios, la representación de los ámbitos territoriales y la naturaleza formal de los telediarios. El OCITV ha contado con la asistencia estadística de Carmen Bravo Llatas, de la Unidad de la Apoyo a la Docencia y la Investigación de la UCM.

The pre-raphaelite female muse in Julia margaret cameron’s “idylls of the king” photographs

There has been little discussion of Julia Margaret Cameron’s Idylls of the King photographs over the past decade. My goal with this paper is to bring her Idylls of the King series back into discussion and address its success and relevance in both art history and literature. Scholars Helmut Gernsheim and Marylu Hill have questioned photography as a means to capture the imaginative content of Tennyson’s Arthurian stories and they declared Cameron’s photographs a failure. I argue that her theatrical style, use of props and costumes, obvious posing of her models, and nod to Victorian tableaux vivants capture the true essence of Tennyson’s epic. Her use of the Pre-Raphaelite female muse to portray the Arthurian characters of Elaine, Guinevere, and Vivien places her photographs in direct correlation with Pre-Raphaelite painting as well as popular literature. Her depictions of Tennyson’s epic poem are highly successful and I believe she achieved her personal goal of ennobling photography to the level of High Art.

Un experimento de enseñanza sobre el límite de una función. Factores determinantes en una trayectoria de aprendizaje

El objetivo del estudio fue identificar características de la construcción del significado de límite de una función en estudiantes de bachillerato (16-17 años). Se diseñó un experimento de enseñanza utilizando una descomposición genética (APOE) del concepto de límite de una función integrando recursos informáticos. Se usó el constructo “Reflexión sobre la Relación Actividad-Efecto” (Simon, Tzur, Heinz y Kinzel, 2004) como una particularización de la abstracción reflexiva para identificar factores que configuran la Trayectoria de Aprendizaje. Los resultados indican que la trayectoria está determinada por la coordinación de las aproximaciones en el dominio y en el rango en diferentes tipos de funciones.

Lower semicontinuity of the feasible set mapping of linear systems relative to their domains

This paper deals with stability properties of the feasible set of linear inequality systems having a finite number of variables and an arbitrary number of constraints. Several types of perturbations preserving consistency are considered, affecting respectively, all of the data, the left-hand side data, or the right-hand side coefficients.

On the existence of fractal strings whose set of dimensions of fractality is not perfect

In this paper we give an example of a nonlattice self-similar fractal string such that the set of real parts of their complex dimensions has an isolated point. This proves that, in general, the set of dimensions of fractality of a fractal string is not a perfect set.

Calmness of the Feasible Set Mapping for Linear Inequality Systems

In this paper we deal with parameterized linear inequality systems in the n-dimensional Euclidean space, whose coefficients depend continuosly on an index ranging in a compact Hausdorff space. The paper is developed in two different parametric settings: the one of only right-hand-side perturbations of the linear system, and that in which both sides of the system can be perturbed. Appealing to the backgrounds on the calmness property, and exploiting the specifics of the current linear structure, we derive different characterizations of the calmness of the feasible set mapping, and provide an operative expresion for the calmness modulus when confined to finite systems. In the paper, the role played by the Abadie constraint qualification in relation to calmness is clarified, and illustrated by different examples. We point out that this approach has the virtue of tackling the calmness property exclusively in terms of the system’s data.

Discontinuity Set Extractor

Disponible en Github: https://github.com/adririquelme/DSE