Modulation of DNA-protein interactions in the P1 and P2 c-myc promoters by two intercalating drugs

8 pages, 9 figures.-- PMID: 9492315 [PubMed].-- Available online Dec 25, 2001.Regulation of transcription from the oncogene c-myc has an important role in the genesis of various tumors. Therefore, c-myc is a potential target for chemotherapy by drugs which are able to modify its activity directly. In this article, we identify the binding sites in the P1 and P2 promoter regions of c-myc for the intercalating antibiotics actinomycin D and elsamicin A. Gel retardation experiments indicate that actinomycin D or elsamicin A binding can inhibit the formation of several DNA-protein complexes. However, relatively low concentrations of elsamicin A, but not actinomycin D, appear to increase the level of binding to the P1 promoter of a protein factor. Using pure Sp1 transcription factor and an oligonucleotide containing the Sp1 putative binding site, we determined that the binding enhancement induced by small amounts of elsamicin was on the Sp1-DNA complex. Run-off transcription experiments in vitro showed that the effect of elsamicin A on Sp1 binding is followed by the maintenance or a relative rise in transcription levels from the P1 promoter of c-myc, while actinomycin D always inhibited the transcription from the P1 c-myc promoter in a concentration-dependent manner. Higher concentrations of elsamicin acted as an inhibitor of the transcription from the P1 start site but not from the P2.This work was financed by grants from the Spanish Dir. Gen. Enseñanza Superior (PB 95-0064) and Dir. Gen. de Investigación Científica y Técnica (PB93/102). The support of the Generalitat de Catalunya through its Centre de Referencia en Biotecnologia is also acknowledged.Peer reviewe

A QUDA-branch to compute disconnected diagrams in GPUs

Although QUDA allows for an efficient computation of many QCD quantities, it is surprinsingly lacking tools to evaluate disconnected diagrams, for which GPUs are specially well suited. We aim to fill this gap by creating our own branch of QUDA, which includes new kernels and functions required to calculate fermion loops using several methods and fermionic regularizations.Comment: 7 pages, 4 figures. Proceedings of the talk given during the code session of the 31st International Symposium on Lattice Field Theory, July 29 - August 3, 2013, Mainz, Germany. Added a missing reference (number [4]

On the stability of θ\theta-methods for DDEs and PDDEs

In this paper, the stability of $\theta$-methods for delay differential equations is studied based on the test equation $y'(t)=-A y(t) + B y(t-\tau)$, where $\tau$ is a constant delay and $A$ is a positive definite matrix. It is mainly considered the case where the matrices $A$ and $B$ are not simultaneosly diagonalizable and the concept of field of values is used to prove a sufficient condition for unconditional stability of these methods and another condition which also guarantees their stability, but according to the step size. The results obtained are also simplified for the case where the matrices $A$ and $B$ are simultaneously diagonalizable and compared with other similar works for the general case. Several numerical examples in which the theory discussed here is applied to parabolic problems given by partial delay differential equations with a diffusion term and a delayed term are presented, too.Comment: 17 pages, 21st IMACS World Congres

Massive Schwinger model at finite θ\theta

Using the approach developed in [V. Azcoiti, G. Di Carlo, A. Galante, V. Laliena, \textit{Phys. Lett.} \textbf{B563}, (2003) 117], we are able to reconstruct the behavior of the massive 1-flavor Schwinger model with a $\theta$ term and a quantized topological charge. We calculate the full dependence of the order parameter with $\theta$. Our results at $\theta = \pi$ are compatible with Coleman's conjecture on the phase diagram of this model.Comment: 8 pages, 8 figure

Resolución de problemas de proporcionalidad directa e inversa por estudiantes de 2º ESO

Este trabajo fin de máster tiene como objetivo estudiar la resolución de problemas de proporcionalidad directa e inversa por estudiantes de 2º ESO. El trabajo se estructura en dos partes. En la primera parte se realiza un estudio longitudinal del currículo y en los libros de texto en el tercer ciclo de Primaria, en ESO y en Bachillerato con relación al tema indicado. En la segunda parte se propone un proceso de estudio sobre proporcionalidad aritmética, que se ha puesto en marcha en un aula de 2º ESO en el marco del Practicum II del Máster. Los resultados extraídos de esta experimentación se fundamentan en un cuestionario construido ad hoc, teniendo en cuenta asimismo las restricciones institucionales. El trabajo concluye con una síntesis, unas conclusiones y unas cuestiones abiertasMáster Universitario en Profesorado de Educación Secundaria por la Universidad Pública de NavarraBigarren Hezkuntzako Irakasletzako Unibertsitate Masterra Nafarroako Unibertsitate Publikoa

Nucleon electromagnetic form factors using lattice simulations at the physical point

We present results for the nucleon electromagnetic form factors using an ensemble of maximally twisted mass clover-improved fermions with pion mass of about 130 MeV. We use multiple sink-source separations and three analysis methods to probe ground-state dominance. We evaluate both the connected and disconnected contributions to the nucleon matrix elements. We find that the disconnected quark loop contributions to the isoscalar matrix elements are small, giving an upper bound of up to 2$\%$ of the connected contribution and smaller than its statistical error. We present results for the isovector and isoscalar electric and magnetic Sachs form factors and the corresponding proton and neutron form factors. By fitting the momentum dependence of the form factors to a dipole form or to the z-expansion we extract the nucleon electric and magnetic radii, as well as, the magnetic moment. We compare our results to experiment as well as to other recent lattice QCD calculations.Comment: 20 pages, 32 figures, and 11 tables. Changes in version 2: Updated to match published versio

Annual report on Sunspot Counting Program 2014

Este programa observación nació a finales del año 2012 en la Universidad de Extremadura con el fin de ampliar aún más nuestra investigación en la reconstrucción de la actividad solar. Desde el 1 de Enero de 2013, nuestros recuentos de manchas solares se han presentado al Real Observatorio de Bélgica (ROB) como contribución a los esfuerzos internacionales de mantener y actualizar el número internacional de Manchas Solares. Para ello, hemos utilizado un pequeño refractor apocromático de 80 mm de diámetro de objetivo y 550 mm de longitud focal, a fin de proyectar una imagen de 150 mm de diámetro en una plantilla. Este informe proporciona un conjunto completo de los datos obtenidos durante el año 2014, con cuatro tablas que muestran nuestros datos. Por otra parte, el índice de referencia de las manchas solares se compara con nuestros resultados. Esperamos que esta publicación sea de utilidad a la comunidad científica que estudia el número de manchas solares: la mayor serie de índices solares derivadas de la observación directa del Sol.This program was born in late 2012 at the University of Extremadura in order to further extend our research in the reconstruction of past solar activity. Since 1st January 2013, our sunspot counts have been submitted to the Royal Observatory of Belgium (ROB) as a contribution to the international effort of maintaining and updating the International Sunspot Number. For this purpose, we have used a small apochromatic refractor –80mm of objective diameter and 550mm of focal length– to project a 150mm diameter image onto a template. In this report, we provide a complete set of data obtained throughout the year 2014, with four Tables showing our data. Moreover, the reference sunspot index is compared with our results. We hope that this publication be useful to the scientific community studying the sunspot number: the longest solar index series derived from direct observation of the Sun