Alternative Splicing at a NAGNAG Acceptor Site as a Novel Phenotype Modifier

Approximately 30% of alleles causing genetic disorders generate premature termination codons (PTCs), which are usually associated with severe phenotypes. However, bypassing the deleterious stop codon can lead to a mild disease outcome. Splicing at NAGNAG tandem splice sites has been reported to result in insertion or deletion (indel) of three nucleotides. We identified such a mechanism as the origin of the mild to asymptomatic phenotype observed in cystic fibrosis patients homozygous for the E831X mutation (2623G>T) in the CFTR gene. Analyses performed on nasal epithelial cell mRNA detected three distinct isoforms, a considerably more complex situation than expected for a single nucleotide substitution. Structure-function studies and in silico analyses provided the first experimental evidence of an indel of a stop codon by alternative splicing at a NAGNAG acceptor site. In addition to contributing to proteome plasticity, alternative splicing at a NAGNAG tandem site can thus remove a disease-causing UAG stop codon. This molecular study reveals a naturally occurring mechanism where the effect of either modifier genes or epigenetic factors could be suspected. This finding is of importance for genetic counseling as well as for deciding appropriate therapeutic strategies

Modeling and optimization of core (p-GaN)-multishell (i-InxGa1-xN/i-GaN/n-Al0.1Ga0.9N /n-GaN) nanowire for photovoltaic applications

International audienc

Diversity and composition of island insects of Bejaia region (Algeria)

The study was conducted on four islands located west of Bejaia (north-eastern Algeria) to collect baseline information about diversity and composition of insects. Data were collected during summer and spring of 2015 using traps, sweep nets and the Japanese umbrella sampling methods. A total of 1691 individuals belonging to 112 species were collected. Totals of 72, 56, 41 and 34 species were recorded in Pisans Island, El Euch Island, Sahel Islet and Ail Islet, respectively. Of the 1,691 individuals recorded, 39.85 %, 30.51 %, 18.03 % and 11.59 % were recorded in Pisans Island, El Euch Island, Sahel Islet and Ail Islet, respectively. Shannon-Weaver index ranged from 2.96 to 3.34 and Equitability between 0.77 and 0.87. The composition of the insect community differed between sampled islands (NMDS, Stress =. 0.013). Eleven (11) insect species composed over 50 % of dissimilarity between islands. Two species (Cassida viridis (L.) and Pheidole pallidula (Nyl.) accounted for more than 5 % of the diversity on all islands. Sorensen's similarity coefficient showed that Pisans and El Euch islands have the highest similarity (45.37 %), while the lowest similarity was recorded between Pisans Island and Sahel Islet (15.53 %)

Influence of ion species of AuSi liquid metal alloy source-focused ion beam on SiO2/Si nanopatterning

International audienc

Investigation on the optical gain and threshold current density of Ga<inf>1&#x2212;x</inf>In<inf>x</inf>As<inf>1&#x2212;y&#x2212;z</inf>N<inf>y</inf>Sb<inf>z</inf> /GaAs strained quantum wells laser

The aim of this work is to exploit the properties of the GaInAsNSb/GaAs alloy compressive highly strain structure. Ga 1-x In x As 1-y-z N y Sb z has been found to be a potentially superior material to GaInAsN for optical fiber communications long wavelength laser (VCSELs) applications. Indeed, this material has the property that it can be grown on a GaAs substrate while having a bandgap smaller than that of GaInAs. We study the influence of nitrogen and antimony on the lattice parameter and then the strain. Also, the effect of these two elements on the optical gain and threshold current density is investigate

Modeling and optimization of core/shell p-i-n Si/Si0.2Ge0.8 nanowire for photovoltaic

International audienceIn this work we propose a modeling and simulation of core/shell p-i-n Si/Si0.2Ge0.8 nanowire for photovoltaic. In the first step of this work, we have compared the core/shell p-i-n homo-junction Si and heterojunction Si/Si0.2Ge0.8 Nanowire (NW) solar cell having a length of 3 mu m and a radius of 0.19 mu m, by studying their current-voltage and external quantum efficiency (EQE). Our results have shown that blending Silicon with 80% of Germanium enhances relatively the short circuit current and efficiency by 3.04% and 8.48% respectively. In other hand, the absorption edge of Silicon NW has extended from 1100 nm to 1200 nm, with a gain of EQE of 15% obtained in this range. In the second part, we have tried to optimize the Si/Si0.2Ge0.8 structure, by varying their radius and length. The corresponding results have indicated that a radius of 0.28 mu m and a length of 10 pm are the optimal geometric parameters for any optimization of such structure. (C) 2017 Elsevier GmbH. All rights reserved

Contacting of Si/SiO2 core/shell nanowires using laser photolithography

International Conference on Technologies and Materials for Renewable Energy, Environment and Sustainability (TMREES), Beirut, LEBANON, APR 21-24, 2017International audienceThe contamination results of extended ion or electron beam irradiation, the type of substrate used, the time required to contact a set of nanowires to gain accurate acknowledge on nanowires properties are the main limitations of focused ion beam (FIB) and electron beam lithography (EBL) techniques for nanowires characterization. We present in this latter, a direct writing technique which is laser photolithography to contact a set of core/shell Si/SiO2 nanowires fabricated by 30 KeV AuSi liquid metal alloy source focused ion beam LMAIS-FIB using Au+ ions to allow forward the electrical characterization of these nanowires