Determination of the phylogenetic range of Sex combs reduced activity in Drosophila melanogaster

The homeotic selector (Hox) genes are required for body patterning in bilaterians. Sex combs reduced (SCR) is a HOX protein in Drosophila melanogaster with two activities: SCRT1 and SCRlab activity required for patterning the prothorax (T1) and labia, respectively. SCRT1 is proposed to be conserved throughout bilaterians while the phylogenetic range of functional conservation of SCRlab is comparatively unknown. The goal of this work was to elucidate the evolutionary time point at which SCR activity changed. CRISPR/Cas9 transgenesis was used to incorporate ɸC31 integrase recombination sites in Drosophila Scr. The ɸC31 integrase could then be used to replace Drosophila Scr with Scr orthologs to study their function. Here, two Scr specific CRISPR guide sequences and a donor template were created to facilitate CRISPR/Cas9 homology-directed repair. Addtionally, Scr orthologs from six phylogenetically diverse species were isolated and incorporated into vectors to facilitate their insertion at Scr

A hierarchical Bayesian model to infer PL(Z) relations using Gaia parallaxes

Aims. We aim at creating a Bayesian model to infer the coefficients of PL or PLZ relations that propagates uncertainties in the observables in a rigorous and well founded way. Methods. We propose a directed acyclic graph to encode the conditional probabilities of the inference model that will allow us to infer probability distributions for the PL and PL(Z) relations. We evaluate the model with several semi-synthetic data sets and apply it to a sample of 200 fundamental mode and first overtone mode RR Lyrae stars for which Gaia DR1 parallaxes and literature Ks-band mean magnitudes are available. We define and test several hyperprior probabilities to verify their adequacy and check the sensitivity of the solution with respect to the prior choice. Results. The main conclusion of this work is the absolute necessity of incorporating the existing correlations between the observed variables (periods, metallicities and parallaxes) in the form of model priors in order to avoid systematically biased results, especially in the case of non-negligible uncertainties in the parallaxes. The tests with the semi-synthetic data based on the data set used in Gaia Collaboration et al. (2017) reveal the significant impact that the existing correlations between parallax, metallicity and periods have on the inferred parameters. The relation coefficients obtained here have been superseded by those presented in Muraveva et al. (2018a), that incorporates the findings of this work and the more recent Gaia DR2 measurements.Comment: 14 pages, 12 figures. Submitted to A&

Quantitative uniqueness for elliptic equations with singular lower order terms

We use a Carleman type inequality of Koch and Tataru to obtain quantitative estimates of unique continuation for solutions of second order elliptic equations with singular lower order terms. First we prove a three sphere inequality and then describe two methods of propagation of smallness from sets of positive measure.Comment: 23 pages, v2 small changes are done and some mistakes are correcte

Costruire in pietra, pratica e storia. Laboratorio di stereotomia - Palermo 2016

Il volume raccoglie i contributi presentati in occasione del seminario introduttivo al Laboratorio di stereotomia, tenutosi presso il Dipartimento di Architettura dell'Università degli studi di Palermo nel mese di aprile del 2016, e un contributo che illustra quest'ultima esperienza. Nel complesso, i diversi saggi ruotano intorno al tema della costruzione in pietra nell'ambito dell'architettura tardogotica, con particolare attenzione alle volte, osservata da diversi punti di vista e ambiti disciplinari che spaziano dalla storia, al disegno, alla storia della costruzione. Ricerca e didattica si intrecciano e concorrono a fare nuova luce su esperienze costruttive di primo piano nella storia dell'architettura europea, secondo una modalità già sperimentata da José Carlos Palacios Gonzalo nel Laboratorio di costruzione gotica dell'Universidad Politecnica di Madrid e replicata a Palermo nel Laboratorio di stereotomiaThis volume collects the contributions presented at the introductory seminar at Laboratory of stereotomy, held at the Department of Architecture of the University of Palermo in April of 2016, and a contribution that illustrates this last experience. All the essays deal with the theme of the stone building in late Gothic architecture, with particular attention to the vaults, observed from different points of view and disciplines ranging from history, to drawing, to construction history . Research and teaching are intertwined and help to shed new light on experiences prominent in the history of European architecture, according to a methodology already tested by José Carlos Gonzalo Palacios in the Gothic building Laboratory of the Universidad Politecnica de Madrid and replicated in Palermo in the Laboratory of stereotomy

Triboelectric characterization of colloidal TiO2 for energy harvesting applications

Nowadays, energy-related issues are of paramount importance. Every energy transformation process results in the production of waste heat that can be harvested and reused, representing an ecological and economic opportunity. Waste heat to power (WHP) is the process of converting the waste heat into electricity. A novel approach is proposed based on the employment of liquid nano colloids. In this work, the triboelectric characterization of TiO2 nanoparticles dispersed in pure water and flowing in a fluorinated ethylene propylene (FEP) pipe was conducted. The idea is to exploit the waste heat to generate the motion of colloidal TiO2 through a FEP pipe. By placing an Al ring electrode in contact with the pipe, it was possible to accumulate electrostatic charges due to the triboelectric effect between the fluid and the inner pipe walls. A peristaltic pump was used to drive and control the flow in order to evaluate the performances in a broad fluid dynamic spectrum. The system generated as output relatively high voltages and low currents, resulting in extracted power ranging between 0.4 and 0.6 nW. By comparing the power of pressure loss due to friction with the extracted power, the electro-kinetic efficiency was estimated to be 20%