On the stability and deformability of top stars

Topological stars, or top stars for brevity, are smooth horizonless static solutions of Einstein-Maxwell theory in 5-d that reduce to spherically symmetric solutions of Einstein-Maxwell-Dilaton theory in 4-d. We study linear scalar perturbations of top stars and argue for their stability and deformability. We tackle the problem with different techniques including WKB approximation, numerical analysis, Breit-Wigner resonance method and quantum Seiberg-Witten curves. We identify three classes of quasi-normal modes corresponding to prompt-ring down modes, long-lived meta-stable modes and what we dub `blind' modes. All mode frequencies we find have negative imaginary parts, thus suggesting linear stability of top stars. Moreover we determine the tidal Love and dissipation numbers encoding the response to tidal deformations and, similarly to black holes, we find zero value in the static limit but, contrary to black holes, we find non-trivial dynamical Love numbers and vanishing dissipative effects at linear order. For the sake of illustration in a simpler context, we also consider a toy model with a piece-wise constant potential and a centrifugal barrier that captures most of the above features in a qualitative fashion

Una strada parco per la "Città Pontina"

Nel volume è presentato un progetto di parco lineare innervato sulla realizzazione di una pista ciclabile che sfrutta il tracciato ferroviario dismesso della tratta Velletri Terracina. Il parco include aree agricole, siti archeologici e di interesse storico e naturalistico ed una serie di cave dismesse di cui si progetta la rinaturalizzazioned il riuso per servizi del parco. Il progetto prevede inoltre risalite meccaniche ai centri antichi sulla Pedemontana Setina.In this volume is presented a draft innervated linear park on the creation of a bike path that takes advantage of the disused railway line is of Velletri Terracina. The park includes agricultural areas, and archaeological sites of historical and natural interest and a series of disused quarries where you plan to reuse the rinaturalizzazioned for park services. The project also includes the ski lifts to the ancient centers on the foothills Setina

The multipolar structure of fuzzballs

We extend and refine a general method to extract the multipole moments of arbitrary stationary spacetimes and apply it to the study of a large family of regular horizonless solutions to ${\cal N}{\,=\,}2$ four-dimensional supergravity coupled to four Abelian gauge fields. These microstate geometries can carry angular momentum and have a much richer multipolar structure than the Kerr black hole. In particular they break the axial and equatorial symmetry, giving rise to a large number of nontrivial multipole moments. After studying some analytical examples, we explore the four-dimensional parameter space of this family with a statistical analysis. We find that microstate mass and spin multipole moments are typically (but not always) larger that those of a Kerr black hole with the same mass and angular momentum. Furthermore, we find numerical evidence that some invariants associated with the (dimensionless) moments of these microstates grow monotonically with the microstate size and display a global minimum at the black-hole limit, obtained when all centers collide. Our analysis is relevant in the context of measurements of the multipole moments of dark compact objects with electromagnetic and gravitational-wave probes, and for observational tests to distinguish fuzzballs from classical black holes.Comment: 29 pages, 1 figur

Autonomous Driving Scenario Generation in Overtake Manoeuvres Through Data Fusion

For an effective study of specific driving scenarios, in particular related to overtaking manoeuvres, developing well-thought-out manoeuvre databases from the acquired data will greatly improve the analysis process. The key point being that identifying clearly the studied scenario and clustering the manoeuvres based on specific sub-cases of this will bring an extra dimension of information that allows to visualise existing correlations between a given set of conditions and the manoeuvres performed under them. This paper expands on how to obtain these databases starting from only from overtaken manoeuvres extracted from experimental data. Consisting in two main procedures, the manoeuvre classification itself, in which a hybrid-classifier that combines both supervised and unsupervised algorithms generates the scenario sub-cases, and the database compilation stage, in where it displays the different types of databases that can be created, based on the aim of the study

BEAT: Bioinformatics Exon Array Tool to store, analyze and visualize Affymetrix GeneChip Human Exon Array data from disease experiments

<p>Abstract</p> <p>Background</p> <p>It is known from recent studies that more than 90% of human multi-exon genes are subject to Alternative Splicing (AS), a key molecular mechanism in which multiple transcripts may be generated from a single gene. It is widely recognized that a breakdown in AS mechanisms plays an important role in cellular differentiation and pathologies. Polymerase Chain Reactions, microarrays and sequencing technologies have been applied to the study of transcript diversity arising from alternative expression. Last generation Affymetrix GeneChip Human Exon 1.0 ST Arrays offer a more detailed view of the gene expression profile providing information on the AS patterns. The exon array technology, with more than five million data points, can detect approximately one million exons, and it allows performing analyses at both gene and exon level. In this paper we describe BEAT, an integrated user-friendly bioinformatics framework to store, analyze and visualize exon arrays datasets. It combines a data warehouse approach with some rigorous statistical methods for assessing the AS of genes involved in diseases. Meta statistics are proposed as a novel approach to explore the analysis results. BEAT is available at <url>http://beat.ba.itb.cnr.it</url>.</p> <p>Results</p> <p>BEAT is a web tool which allows uploading and analyzing exon array datasets using standard statistical methods and an easy-to-use graphical web front-end. BEAT has been tested on a dataset with 173 samples and tuned using new datasets of exon array experiments from 28 colorectal cancer and 26 renal cell cancer samples produced at the Medical Genetics Unit of IRCCS Casa Sollievo della Sofferenza.</p> <p>To highlight all possible AS events, alternative names, accession Ids, Gene Ontology terms and biochemical pathways annotations are integrated with exon and gene level expression plots. The user can customize the results choosing custom thresholds for the statistical parameters and exploiting the available clinical data of the samples for a multivariate AS analysis.</p> <p>Conclusions</p> <p>Despite exon array chips being widely used for transcriptomics studies, there is a lack of analysis tools offering advanced statistical features and requiring no programming knowledge. BEAT provides a user-friendly platform for a comprehensive study of AS events in human diseases, displaying the analysis results with easily interpretable and interactive tables and graphics.</p

The puzzling properties of the MACS1149-JD1 galaxy at z=9.11

We analyze new JWST NIRCam and NIRSpec data on the redshift 9.11 galaxy MACS1149-JD1. Our NIRCam imaging data reveal that JD1 comprises three spatially distinct components. Our spectroscopic data indicate that JD1 appears dust-free but is already enriched, $12 + \log {\rm (O/H) } = 7.90^{+0.04}_{-0.05}$. We also find that the Carbon and Neon abundances in JD1 are below the solar abundance ratio. Particularly the Carbon under-abundance is suggestive of recent star formation where Type~II supernovae have already enriched the ISM in Oxygen but intermediate mass stars have not yet enriched the ISM in Carbon. A recent burst of star formation is also revealed by the star formation history derived from NIRCam photometry. Our data do not reveal the presence of a significant amount of old populations, resulting in a factor of $\sim7\times$ smaller stellar mass than previous estimates. Thus, our data support the view that JD1 is a young galaxy.Comment: Accepted for publicatio

Universidad y tecnologías: el conocimiento en la sociedad de la información y el aprendizaje colaborativo

Este trabajo continúa la línea de investigaciones propias anteriores que aborda la problemática relacionada con la formación académica de calidad. En comunicaciones previas, se ha destacado que las TIC (Tecnologías de Información y Comunicación) son ya herramientas de uso frecuente en todos los ámbitos de la educación, que modifican las formas de aprender y enseñar - y también el acceso a la información y al conocimiento. Aún más, las Tecnologías de la Información han optimizado el acercamiento al conocimiento hasta llegar a su gestión, dando origen a las Tecnologías del Aprendizaje y del Conocimiento (TAC). Este “aprendizaje aumentado”, que además incluye las denominadas TEP (Tecnologías de Empoderamiento y Participación), lleva al docente a una búsqueda incesante de la integración de la tecnología en la enseñanza con el contenido tratado, combinando permanentemente decisiones pedagógicas con los conocimientos construidos en el aula. Se busca, entonces, posibilitar la incorporación de nuevas tecnologías que favorezcan ambos, el aprendizaje autónomo del estudiante universitario y su participación en la generación del conocimiento en un mundo de cambios constantes. Así, el propósito de nuestro trabajo consiste en evaluar las herramientas tecnológicas disponibles con el objeto de implementar dispositivos didácticos que tiendan a la formación de calidad de un estudiante activo, participativo e independiente.Dirección de Educación a Distancia, Innovación en el aula y TIC (EAD