Globular Clusters: DNA of Early-Type galaxies?

This paper explores if the mean properties of Early-Type Galaxies (ETG) can be reconstructed from "genetic" information stored in their GCs (i.e., in their chemical abundances, spatial distributions and ages). This approach implies that the formation of each globular occurs in very massive stellar environments, as suggested by some models that aim at explaining the presence of multi-populations in these systems. The assumption that the relative number of globular clusters to diffuse stellar mass depends exponentially on chemical abundance, [Z/H], and the presence of two dominant GC sub-populations blue and red, allows the mapping of low metallicity halos and of higher metallicity (and more heterogeneous) bulges. In particular, the masses of the low-metallicity halos seem to scale up with dark matter mass through a constant. We also find a dependence of the globular cluster formation efficiency with the mean projected stellar mass density of the galaxies within their effective radii. The analysis is based on a selected sub-sample of galaxies observed within the ACS Virgo Cluster Survey of the {\it Hubble Space Telescope}. These systems were grouped, according to their absolute magnitudes, in order to define composite fiducial galaxies and look for a quantitative connection with their (also composite) globular clusters systems. The results strengthen the idea that globular clusters are good quantitative tracers of both baryonic and dark matter in ETGs.Comment: 20 pages, 28 figures and 5 table

Identification and functional analysis of novel phosphorylation sites in the RNA surveillance protein Upf1.

One third of inherited genetic diseases are caused by mRNAs harboring premature termination codons as a result of nonsense mutations. These aberrant mRNAs are degraded by the Nonsense-Mediated mRNA Decay (NMD) pathway. A central component of the NMD pathway is Upf1, an RNA-dependent ATPase and helicase. Upf1 is a known phosphorylated protein, but only portions of this large protein have been examined for phosphorylation sites and the functional relevance of its phosphorylation has not been elucidated in Saccharomyces cerevisiae. Using tandem mass spectrometry analyses, we report the identification of 11 putative phosphorylated sites in S. cerevisiae Upf1. Five of these phosphorylated residues are located within the ATPase and helicase domains and are conserved in higher eukaryotes, suggesting a biological significance for their phosphorylation. Indeed, functional analysis demonstrated that a small carboxy-terminal motif harboring at least three phosphorylated amino acids is important for three Upf1 functions: ATPase activity, NMD activity and the ability to promote translation termination efficiency. We provide evidence that two tyrosines within this phospho-motif (Y-738 and Y-742) act redundantly to promote ATP hydrolysis, NMD efficiency and translation termination fidelity

Rasgos geológicos del skarn Loma Marcelo

El skarn Loma Marcelo representa un evento geológico de características únicas en el ámbito del basamento proterozoico de las Sierras Australes de la provincia de Buenos Aires, Argentina. Rodeado por milonitas y cataclasitas graníticas, el skarn, caracterizado como de tipo cálcico,presenta paragénesis minerales de posible afinidad ígnea con circones zonados. La paragénesis calcosilicática está principalmente integrada por hedenbergita diopsídica y grosularia andradítica y, en menor proporción, por anfíbol, epidoto, cuarzo, titanita y wollastonita -vesubianita. Los modelos genéticos sostenidos hasta la actualidad indicaban que el skarn Loma Marcelo estaba relacionado a la intrusión de granitoides en rocas carbonáticas más antiguas, pudiendo existir una alternativa genética diferente en la cu.al los fluidos provenientes de la deformación-metamorfismo dinámico sobreimpuestos a estas rocas hayan sido los que provocaron los procesos de intercambio metasomático. Nuevos estudios estructurales junto con datos isotópicos inéditos han permitido postular, en forma preliminar,que la roca carbonática del skarn Loma Marcelo conforma un cuerpo carbonatítico intruido en los granitoides del basamento proterozoico del área delos cerros Pan de Azúcar-del Corral. Los fluidos provenientes de este magma carbonatítico serían los responsables de la génesis del skarn Loma Marcelo.XX Congreso Geológico Boliviano realizado en La Paz, Bolivia, del 1 al 4 de octubre del 2012

Impact of 3D EM model configuration on the direct optimization of microstrip structures

We apply the classical Nelder-Mead optimization algorithm to a low fidelity EM model, using different mesh and bounding-box configurations. We demonstrate that the interaction of the coarse mesh with the bounding box size can determine whether the optimization is successful or not.ITESO, A.C.Intel Lab

Safety of Oscillatingâ Rotating Powered Brushes Compared to Manual Toothbrushes: A Systematic Review

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141660/1/jper0005.pd

Small volume expansion of almost supersymmetric large N theories

We consider the small-volume dynamics of nonsupersymmetric orbifold and orientifold field theories defined on a three-torus, in a test of the claimed planar equivalence between these models and appropriate supersymmetric ``parent models". We study one-loop effective potentials over the moduli space of flat connections and find that planar equivalence is preserved for suitable averages over the moduli space. On the other hand, strong nonlinear effects produce local violations of planar equivalence at special points of moduli space. In the case of orbifold models, these effects show that the "twisted" sector dominates the low-energy dynamics.Comment: 20 pages, 3 figures; added references, minor change