Very accurate Distances and Radii of Open Cluster Cepheids from a Near-Infrared Surface Brightness Technique

We have obtained the radii and distances of 16 galactic Cepheids supposed to be members in open clusters or associations using the new optical and near-infrared calibrations of the surface brightness (Barnes-Evans) method given by Fouque & Gieren (1997). We discuss in detail possible systematic errors in our infrared solutions and conclude that the typical total uncertainty of the infrared distance and radius of a Cepheid is about 3 percent in both infrared solutions, provided that the data are of excellent quality and that the amplitude of the color curve used in the solution is larger than ~0.3 mag. We compare the adopted infrared distances of the Cepheid variables to the ZAMS-fitting distances of their supposed host clusters and associations and find an unweighted mean value of the distance ratio of 1.02 +- 0.04. A detailed discussion of the individual Cepheids shows that the uncertainty of the ZAMS-fitting distances varies considerably from cluster to cluster. We find clear evidence that four Cepheids are not cluster members (SZ Tau, T Mon, U Car and SV Vul) while we confirm cluster membership for V Cen and BB Sgr for which the former evidence for cluster membership was only weak. After rejection of non-members, we find a weighted mean distance ratio of 0.969 +- 0.014, with a standard deviation of 0.05, which demonstrates that both distance indicators are accurate to better than 5%, including systematic errors, and that there is excellent agreement between both distance scales.Comment: LaTeX, 11 Figures, 5 Tables, to be published in The Astrophysical Journal, Oct. 10, 1997 issu

The Hubble Constant from the Fornax Cluster Distance

Type Ia supernovae are the best cosmological standard candles available. The intrinsic scatter of their decline-rate- and colour-corrected peak brightnesses in the Hubble diagram is within observational error limits, corresponding to an uncertainty of only 3km/s/Mpc of the Hubble constant. Any additional uncertainty, resulting from peak-brightness calibration, must be kept small by measuring distances to nearby host galaxies most precisely. A number of different distance determinations of the Fornax cluster of galaxies agree well on a distance modulus of 31.35+-0.04mag (18.6+-0.3Mpc). This leads to accurate absolute magnitudes of the well-observed Fornax type Ia SNe SN1980N, SN1981D, and SN1992A and finally to a Hubble constant of H_0=72+-6km/s/Mpc.Comment: 5 pages, 1 figure, to be published in: Science in the VLT Era and Beyond. ESO VLT Opening Symposium, Springer, in press; typos remove

Causality in 3D Massive Gravity Theories

We study the constraints coming from local causality requirement in various $2+1$ dimensional dynamical theories of gravity. In topologically massive gravity, with a single parity non-invariant massive degree of freedom, and in new massive gravity, with two massive spin-$2$ degrees of freedom, causality and unitarity are compatible with each other and both require the Newton's constant to be negative. In their extensions, such as the Born-Infeld gravity and the minimal massive gravity the situation is similar and quite different from their higher dimensional counterparts, such as quadratic (e.g., Einstein-Gauss-Bonnet) or cubic theories, where causality and unitarity are in conflict. We study the problem both in asymptotically flat and asymptotically anti-de Sitter spaces.Comment: This version has significant improvements: causality discussion of all the well-known gravity theories in flat space is extended to the AdS space, references added, 29 pages, latest version matches the published on

Socioemotional wealth preservation in family firms

In this article, we review literature on socioemotional wealth. We explain how the concept of socioemotional wealth builds on previous family firm research showing that family-owners derive utility from the nonfinancial aspects of their firm. We also discuss how family firms' need for socioemotional wealth preservation explains behavioral differences between family and nonfamily firms in managerial decision making. Finally, we discuss the current state of socioemotional wealth research and propose potential directions for future research

Phreatomagmatic activity and associated hydrothermal processes in the lamproitic Volcano of Cancarix (Southeast Spain)

The study of the Cancarix volcano structure (Sierra de las Cabras, SE Spain) and the regional observations in similar lamproite volcanoes suggest that these magmas were emplaced during the Miocene in relation to transtensive structures at the North end of the Betic Cordillera. These structures were able to reactivate previous basement faults which facilitated the ascending circulation of enriched ultrapotassic magma. Two episodes are distinguished: 1) explosive volcanism due to the interaction between magma and groundwater from the karstic system of the host carbonate rocks, which generated a phreatomagmatic-effusive complex and 2) volcanic-building with crystal-rich magma. The phreatomagmatic breccia distribution is conditioned by the tectonic structure of the host rock, with maximum thickness over the marls basement, mechanically less competent, which is controlling the preferential magma movement towards the S-SE. Chemical, mineralogical and textural study of the host rocks and the volcanic products indicates that following the magmatic activity hydrothermal processes ocurred, with: (1) the genesis of new minerals (namely, saponitic smectite and serpentine minerals) in the host rock clasts from the phreatomagmatic breccia; and (2) the recrystallisation of dolomite and amorphous silica growing up to 20 m from the contact in porous carbonates. In contrast, marls and micritic carbonates show no recrystallisation, only a slight enrichment of Mg and some exotic elements, limited to the first few metres.El estudio de la estructura del Volcán de Cancarix (Sierra de las Cabras, SE España) y las observaciones regionales en volcanes lamproíticos similares sugieren que el emplazamiento de los magmas tuvo lugar durante el Mioceno en relación con estructuras transtensivas en el extremo Norte de la Cordillera Bética. Estas estructuras favorecieron la reactivación de fallas previas del basamento que facilitaron la circulación ascendente de magmas enriquecidos en Mg y K. Se han diferenciado dos episodios de emisión de material en el Volcán de Cancarix: 1) vulcanismo explosivo debido a la interacción del magma con el agua subterránea procedente del sistema kárstico de los carbonatos que componen la roca caja, que generó un complejo freatomagmático (brechas y lavas) y 2) una etapa de vulcanismo efusivo con un magma rico en cristales que dio lugar al domo lamproítico. La distribución de la brecha freatomagmática estuvo condicionada por la estructura tectónica de la roca caja, con un máximo espesor sobre las margas, mecánicamente menos competentes. En consequencia, la dirección preferente de avance del magma fue hacia el S-SE, donde las margas son predominantes. El estudio geoquímico, mineralógico y textural de la roca caja y del material volcánico indica que tras la actividad volcánica, hubo una actividad hidrotermal que produjo la alteración de los materiales con: (1) la génesis de nuevos minerales (esmectitas saponíticas y minerales del grupo de la serpentina) en los clastos de la roca caja incorporados a la brecha freatomagmática y (2) la recristalizacion de dolomita y sílice amorfa en las rocas carbonatadas más porosas desde el contacto hasta una distancia de aproximadamente 20 m. Sin embargo, las margas y los carbonatos micríticos no muestran recristalización, únicamente un ligero enriquecimiento en Mg y algunos elementos traza en los primeros metros cerca del contacto con la brecha freatomagmática y la lamproita

Confirmation Of Two New Galactic Bulge Globular Clusters: FSR 19 and FSR 25

Globular clusters (GCs) in the Milky Way (MW) bulge are very difficult to study because: i) they suffer from the severe crowding and galactic extinction; which are characteristic of these inner Galactic regions ii) they are more prone to be affected by dynamical processes. Therefore, they are relatively faint and difficult to map. However, deep near-infrared photometry like that provided by the VISTA Variables in the Via L\'actea Extended Survey (VVVX) is allowing us to map GCs in this crucial yet relatively uncharted region. Our results confirm with high confidence that both FSR 19 and FSR 25 are genuine MW bulge GCs. Each of the performed tests and resulting parameters provides clear evidence for the GC nature of these targets. We derive distances of 7.2$\pm$0.7 kpc and D=7.0$\pm$0.6 (corresponding to distance moduli of 14.29$\pm$0.08 and 14.23$\pm$0.07) for FSR 19 and FSR 25, respectively. Their ages and metallicities are 11 Gyr and [Fe/H]= -0.5 dex for both clusters, which were determined from Dartmouth and PARSEC isochrone fitting. The integrated luminosities are M$_{Ks}$(FSR 19) = -7.72 mag and M$_{Ks}$(FSR 25) = -7.31 mag which places them in the faint tail of the GC Luminosity Function. By adopting a King profile for their number distribution, we determine their core and tidal radii ($r_c$, $r_t$). For FSR 19, r$_{c}$= 2.76$\pm$0.36 pc and r$_{t}$=5.31$\pm$0.49 pc, while FSR 25 appears more extended with r$_{c}$= 1.92$\pm$0.59 pc and r$_{t}$=6.85$\pm$1.78 pc. Finally their mean GC PMs (from Gaia EDR3) are $\mu_{\alpha^\ast}$= -2.50 $\pm$0.76 mas $yr^{-1}$, $\mu_{\delta}$= -5.02 $\pm$0.47 mas $yr^{-1}$ and $\mu_{\alpha^\ast}$= -2.61 $\pm$ 1.27 mas $yr^{-1}$ , $\mu_{\delta}$= -5.23 $\pm$0.74 mas $yr^{-1}$ for FSR 19 and FSR 25, respectively.

Proapoptotic and antiinvasive activity of Rac1 small molecule inhibitors on malignant glioma cells

Malignant gliomas are characterized by an intrinsic ability to invade diffusely throughout the normal brain tissue. This feature contributes mainly to the failure of existing therapies. Deregulation of small GTPases signaling, in particular Rac1 activity, plays a key role in the invasive phenotype of gliomas. Here we report the effect of ZINC69391, a specific Rac1 inhibitor developed by our group, on human glioma cell lines LN229 and U-87 MG. ZINC69391 is able to interfere with the interaction of Rac1 with Dock180, a relevant Rac1 activator in glioma invasion, and to reduce Rac1-GTP levels. The kinase Pak1, a downstream effector of Dock180–Rac1 signaling, was also downregulated upon ZINC69391 treatment. ZINC69391 reduced cell proliferation, arrested cells in G1 phase, and triggered apoptosis in glioma cells. Importantly, ZINC69391 dramatically affected cell migration and invasion in vitro, interfering with actin cytoskeleton dynamics. We also evaluated the effect of analog 1A-116, a compound derived from ZINC69391 structure. 1A-116 showed an improved antiproliferative and antiinvasive activity on glioma cells. These findings encourage further preclinical testing in clinically relevant animal models.Fil: Cardama, Georgina Alexandra. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Oncología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: González, Nazareno. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Oncología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ciarlantini, Matias Sebastián. Instituto Nacional de Tecnología Industrial; ArgentinaFil: Gandolfi Donadío, Lucía. Instituto Nacional de Tecnología Industrial; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Comin, Maria Julieta. Instituto Nacional de Tecnología Industrial; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alonso, Daniel Fernando. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Oncología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lorenzano Menna, Pablo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Oncología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gomez, Daniel Eduardo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Oncología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Historical Biogeography of the Leptodactylus fuscus Group (Anura, Leptodactylidae): Identification of Ancestral Areas and Events that Modeled their Distribution

The objective of the present study was to reconstruct the biogeographic history of the monophyletic group Leptodactylus fuscus. We carried out two complementary historical biogeographic approaches: one estimates the ancestral areas with the statistical dispersion and vicariance method (S-DIVA). The other detects disjoint distributions among sister groups, which provides information about barriers that separate populations through a spatial analysis of vicariance (VIP method). For that, we used a database of species presence records and a topology of a phylogenetic cladogram, both obtained from updated published data that incorporates the current phylogenetic, taxonomic and distributional arrangements for the group. For the analysis of ancestral areas, the following areas of the L. fuscus group distribution were used: the Carribean, Chacoan, Parana, Amazonian and North American in Pacific subregions. The optimal reconstruction obtained with S-DIVA showed five vicariance events, two extinctions and 50 dispersals. The spatial analysis of vicariance revealed 19 disjointed sibling nodes and two distributions on nodes removed in the consensus tree. The results suggest that the ancestor of the Leptodactylus fuscus group occupied large areas within the Amazon and Chacoan subregions. Due to several dispersal events, the ancestor distribution range may have expanded to the Caribbean subregion. This expansion could have occurred during wetter periods, when forests were more extensive, which would have allowed the invasion of open habitats within humid forest systems. It is important to note that ecological factors and marine transgressions that occurred during the Miocene could have had a great influence on the current distribution of the group.Fil: Caffaro, Matias Exequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Medina, Regina Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biodiversidad Neotropical. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical. Instituto de Biodiversidad Neotropical; Argentina. Pontificia Universidad Católica de Chile; ChileFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Diaz Gomez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentin