Non-linear metric perturbation enhancement of primordial gravitational waves

We present the evolution of the full set of Einstein equations during preheating after inflation. We study a generic supersymmetric model of hybrid inflation, integrating fields and metric fluctuations in a 3-dimensional lattice. We take initial conditions consistent with Eintein's constraint equations. The induced preheating of the metric fluctuations is not large enough to backreact onto the fields, but preheating of the scalar modes does affect the evolution of vector and tensor modes. In particular, they do enhance the induced stochastic background of gravitational waves during preheating, giving an energy density in general an order of magnitude larger than that obtained by evolving the tensors fluctuations in an homogeneous background metric. This enhancement can improve the expectations for detection by planned gravitational waves observatories.Comment: 5 pages, 4 eps figures, matches Phys. Rev. Lett. versio

Preparation of Dendrimeric antigen-silica particle composites

Abstract para Comunicación en el congreso tipo cartelThe desing and synthesis of new materials for biomedical applications is a high-priority research topic in a great number of biomedical areas. Moreover, advances in the fabrication of these materials are of growing interest in antibody-based diagnostic techniques. These materiasl consist in a solid support anchored with the desired bioactive molecules. Such solid supports need to be robust enough and posses surrounding reactive groups that enables the chemical bonding of the active components. Furthermore, these materials need to meet certain conditions to ensure biocompatibility and non-toxicity. In this sense, silica nanoparticles have been widely used. Our research involves the study of hybrid materials that combine the high functionality of silica nanoparticles with well defined size and controlled peripheral multivalence components like dendrimers. Dendrimer antigens, which are synthetic antigens where the role of the carrier protein is performed by a dendrimer, were supported on silica particles. These organic-inorganic hybrid materials were carefully characterized and the preparation methodology was confirmed to be highly reproducible. Such hybrid materials were used for the in vitro diagnosis of patien allergic to amoxicillin.1 Herein, we present the preparation of novel nano-materials containing new antigenics determinants of antibiotics. Amoxicillin, bencyl penicillin, clavulanic acid and its derivates were used to prepares diferent dendrimeric antigens supported on silca particles. These particles will be used to specifically and selectively detect and quantify IgE in sera from allergic patients. These new materials are a promising candidate to improve the practice of in vitro clinical diagnosis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

O uso ritual da ayahuasca

Book review of O uso ritual da ayahuasca. Beatriz Caiuby Labate & Wladimyr Sena Araújo (editors). Campinas (São Paulo, Brazil): Mercado das Letras / FAPESP, 2002. 686 pp. ISBN 85 85725-91-5

Optical photometry of the UCM Lists I and II

We present Johnson B CCD photometry for the whole sample of galaxies of the Universidad Complutense de Madrid (UCM) Survey Lists I and II. They constitute a well-defined and complete sample of galaxies in the Local Universe with active star formation. The data refer to 191 S0 to Irr galaxies at an averaged redshift of 0.027, and complement the already published Gunn r, J and K photometries. In this paper the observational and reduction features are discussed in detail, and the new colour information is combined to search for clues on the properties of the galaxies, mainly by comparing our sample with other surveys.Comment: 14 pages, 7 PostScript figures, accepted for publication in A&AS, also available vi ftp at ftp://cutrex.fis.ucm.es/pub/OUT/pag/PAPERS

Plasmids in the aphid endosymbiont Buchnera aphidicola with the smallest genomes. A puzzling evolutionary story.

Buchnera aphidicola, the primary endosymbiont of aphids, has undergone important genomic and biochemical changes as an adaptation to intracellular life. The most important structural changes include a drastic genome reduction and the amplification of genes encoding key enzymes for the biosynthesis of amino acids by their translocation to plasmids. Molecular characterization through different aphid subfamilies has revealed that the genes involved in leucine and tryptophan biosynthesis show a variable fate, since they can be located on plasmids or on the chromosome in different lineages. This versatility contrasts with the genomic stasis found in three distantly related B. aphidicola strains already sequenced. We present the analysis of three B. aphidicola strains (BTg, BCt and BCc) belonging to aphids from different tribes of the subfamily Lachninae, that was estimated to harbour the bacteria with the smallest genomes. The presence of both leucine and tryptophan plasmids in BTg, a chimerical leucine-tryptophan plasmid in BCt, and only a leucine plasmid in BCc, indicates the existence of many recombination events in a recA minus bacterium. In addition, these B. aphidicola plasmids are the simplest described in this species, indicating that plasmids are also involved in the genome shrinkage process

A neurodevelopmental perspective to improve innovation in preventive treatment of substance use disorders

Background: Midbrain dopaminergic neurons have been associated with substance use disorders (Blaess & Ang, 2015). Understanding their neurodevelopment during early stages of life is fundamental for innovating preventive care treatments. The animal model Monodelphis domestica has been proposed as an excellent candidate to study neurodevelopmental changes due to the ease of access to see changes in their embryonic development (Mate et al., 1994). The purpose of our study is to inform how brain cells, including and especially dopaminergic neurons, mature by quantifying their number during early development. Additionally, the study aims to compare different midbrain areas and track neurodevelopmental changes across early development. Methods: Monodelphis brains were collected at different developmental times points, brains were sliced, and brain sections processed following standard immunohistochemistry and other staining protocols to visualize different protein markers. ImageJ and Zen software were used to conduct area analysis and neuronal quantification. A modified stereological approach developed by our lab was utilized for precise neuronal quantification. A descriptive analysis was utilized to compare anatomical and neuronal numerical differences across different developmental stages. Inter-rater reliability was utilized to reduce bias during the neuronal quantification process. Results: A preliminary analysis from a previous study (Perez et al., 2021) revealed anatomical differences in area and volume across three different stages, embryonic day 14 (area= 27260.36 μm, m= 381.376, V=81781.0735 um^3), postnatal day 1 (49917.28 μm, m= 404.12, V= 149751.827 μm^3), and postnatal day 6 (81866.66 μm, m=166.016, V= 245599.9853 μm^3). Neuronal and area differences from the stages of postnatal day 21, 30, 8 weeks and 23 weeks will be included once inter-rater reliability is established

VIP contribution to the decidualization program: regulatory T cell recruitment

During early pregnancy, the human uterus undergoes profound tissue remodeling characterized by leukocyte invasion and production of proinflammatory cytokines, followed by tissue repair and tolerance maintenance induction. Vasoactive intestinal peptide (VIP) is produced by trophoblast cells and modulates the maternal immune response toward a tolerogenic profile. Here, we evaluated the contribution of the VIP/VPAC to endometrial renewal, inducing decidualization and the recruitment of induced regulatory T cells (iTregs) that accompany the implantation period. For that purpose, we used an in vitro model of decidualization with a human endometrial stromal cell line (HESC) stimulated with progesterone (P4) and lipopolysaccharide (LPS) simulating the inflammatory response during implantation and human iTregs (CD4+CD25+FOXP3+) differentiated from naïve T cells obtained from peripheral blood mononuclear cells of fertile women. We observed that VIP and its receptor VPAC1 are constitutively expressed in HESCs and that P4 increased VIP expression. Moreover, in HESC VIP induced expression of RANTES (CCL5), one of the main chemokines involved in T cell recruitment, and this effect is enhanced by the presence of P4 and LPS. Finally, assays of the migration of iTregs toward conditioned media from HESCs revealed that endogenous VIP production induced by P4 and LPS and RANTES production were involved, as anti-RANTES neutralizing Ab or VIP antagonist prevented their migration. We conclude that VIP may have an active role in the decidualization process, thus contributing to recruitment of iTregs toward endometrial stromal cells by increasing RANTES expression in a P4-dependent manner.Fil: Grasso, Esteban Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Paparini, Daniel Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Agüero, Mariana. Universidad de Buenos Aires; ArgentinaFil: Mor, Gil. University of Yale; Estados UnidosFil: Perez Leiros, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Ramhorst, Rosanna Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin