Priming effects of arithmetic signs in 10‐ to 15‐year‐old children

International audienceIn this research, 10- to 12- and 13- to 15-year-old children were presented with very simple addition and multiplication problems involving operands from 1 to 4. Critically, the arithmetic sign was presented before the operands in half of the trials, whereas it was presented at the same time as the operands in the other half. Our results indicate that presenting the 'x' sign before the operands of a multiplication problem does not speed up the solving process, irrespective of the age of children. In contrast, presenting the '+' sign before the operands of an addition problem facilitates the solving process, but only in 13 to 15-year-old children. Such priming effects of the arithmetic sign have been previously interpreted as the result of a pre-activation of an automated counting procedure, which can be applied as soon as the operands are presented. Therefore, our results echo previous conclusions of the literature that simple additions but not multiplications can be solved by fast counting procedures. More importantly, we show here that these procedures are possibly convoked automatically by children after the age of 13 years. At a more theoretical level, our results do not support the theory that simple additions are solved through retrieval of the answers from long-term memory by experts. Rather, the development of expertise for mental addition would consist in an acceleration of procedures until automatization

Transfert de la notion de développement durable dans les politiques publiques centroaméricaines : lecture croisée des évolutions de référentiels et des trajectoires de politiques rurales au Costa Rica et au Nicaragua

Depuis le Sommet de la Terre en 1992, le développement durable (DD) s'est imposé comme le paradigme pour une orientation renouvelée des politiques publiques, notamment celles affectant les espaces ruraux. Adopté par de nombreuses institutions nationales et internationales, ce référentiel justifie un nombre croissant de politiques nationales. Vingt ans plus tard, en Amérique Centrale, des difficultés subsistent pour atteindre les trois dimensions du DD et la mise en oeuvre des politiques rurales intégrant effectivement le DD demeure un enjeu crucial. Notre communication vise à analyser comment certains pays centroaméricains ont intégré le référentiel du DD dans leurs politiques rurales et pourquoi ce concept s'est intégré de manière différenciée selon les pays. Nous répondons à ces questions sur la base d'une analyse comparée des trajectoires de politiques publiques de deux pays aux conditions contrastés : le Costa Rica, pays à revenus intermédiaires reconnu pour son modèle social et ses politiques environnementales, et le Nicaragua, pays à faible revenu, marqué par de fortes inégalités et en proie à la dégradation de ses ressources naturelles. Nous montrons que le concept de DD a été effectivement incorporé dans les cadres de politiques publiques rurales au Costa Rica et Nicaragua. Cette incorporation s'est opérée de manière différenciée dans les deux pays. Quatre facteurs permettent d'expliquer cette situation : le poids relatif des différents secteurs au sein du système politico-administratif, la relation entre les acteurs publics et la coopération internationale, le degré d'avancement du processus de décentralisation, et les capacités des acteurs à défendre leurs intérêts. Dès lors, le nouveau cadre de politique de développement territorial centroaméricain pourrait constituer une voie d'avenir pour surmonter les difficultés actuelles, et favoriser le développement territorial rural de manière durable. (Résumé d'auteur

O dente, a palma

O dente, a palma - tradução de artig

Hot Carrier Solar Cell: From Simulation to Devices

International audienceSingle junction III-V heterostructures based devices could overtake the Shockley-Queisser limit if thermalisation of photogenerated carriers can be strongly limited as in the hot carrier solar cell concept. Previous modelling and experiments have shown the interest of Multiple Quantum Wells heterostructures in the antimonide system and the importance of very thin structures. In this paper we report new data on the thermalisation rates in antimonide and phosphide heterostructures measured at ambient temperature. For the first time electrical control of hot carrier population is performed on hot carrier heterostructures device

Three years pilot of spinal muscular atrophy newborn screening turned into official program in Southern Belgium

Motor neuron disease; Population screeningMalaltia de la neurona motora; Cribratge de poblacióEnfermedad de la neurona motora; Cribado de poblaciónThree new therapies for spinal muscular atrophy (SMA) have been approved by the United States Food and Drug Administration and the European Medicines Agency since 2016. Although these new therapies improve the quality of life of patients who are symptomatic at first treatment, administration before the onset of symptoms is significantly more effective. As a consequence, newborn screening programs have been initiated in several countries. In 2018, we launched a 3-year pilot program to screen newborns for SMA in the Belgian region of Liège. This program was rapidly expanding to all of Southern Belgium, a region of approximately 55,000 births annually. During the pilot program, 136,339 neonates were tested for deletion of exon 7 of SMN1, the most common cause of SMA. Nine SMA cases with homozygous deletion were identified through this screen. Another patient was identified after presenting with symptoms and was shown to be heterozygous for the SMN1 exon 7 deletion and a point mutation on the opposite allele. These ten patients were treated. The pilot program has now successfully transitioned into the official neonatal screening program in Southern Belgium. The lessons learned during implementation of this pilot program are reported.This pilot study is supported by AveXis, Biogen, Roche, the ABMM (Association Belge contre les Maladies neuro-Musculaires), Minister's Office Alda GREOLI (Wallonia-Brussels Community) and donations from individuals

Microfluidic extraction and digital quantification of circulating cell-free DNA from serum

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The Respiratory Syncytial Virus G Protein Conserved Domain Induces a Persistent and Protective Antibody Response in Rodents

Respiratory syncytial virus (RSV) is an important cause of severe upper and lower respiratory disease in infants and in the elderly. There are 2 main RSV subtypes A and B. A recombinant vaccine was designed based on the central domain of the RSV-A attachment G protein which we had previously named G2Na (aa130–230). Here we evaluated immunogenicity, persistence of antibody (Ab) response and protective efficacy induced in rodents by: (i) G2Na fused to DT (Diphtheria toxin) fragments in cotton rats. DT fusion did not potentiate neutralizing Ab responses against RSV-A or cross-reactivity to RSV-B. (ii) G2Nb (aa130–230 of the RSV-B G protein) either fused to, or admixed with G2Na. G2Nb did not induce RSV-B-reactive Ab responses. (iii) G2Na at low doses. Two injections of 3 µg G2Na in Alum were sufficient to induce protective immune responses in mouse lungs, preventing RSV-A and greatly reducing RSV-B infections. In cotton rats, G2Na-induced RSV-reactive Ab and protective immunity against RSV-A challenge that persisted for at least 24 weeks. (iv) injecting RSV primed mice with a single dose of G2Na/Alum or G2Na/PLGA [poly(D,L-lactide-co-glycolide]. Despite the presence of pre-existing RSV-specific Abs, these formulations effectively boosted anti-RSV Ab titres and increased Ab titres persisted for at least 21 weeks. Affinity maturation of these Abs increased from day 28 to day 148. These data indicate that G2Na has potential as a component of an RSV vaccine formulation

On the Compensation of RF Impairments with Multiple Antennas in SIMO OFDM systems

International audienceThis paper provides an analysis of the impact of radio frequency (RF) front end impairments (I/Q gain and phase imbalance, phase noise, non-linear distortion and direct current offset) on the performance of a single input multiple output orthogonal frequency division multiplexing (SIMO OFDM) receiver. We developed a new estimation/compensation scheme to jointly compensate for the effect of multipath and RF nonidealities on baseband signals in the special case of Zero-IF receivers. Some first results illustrating this approach are presented for a 4 antenna 802.11g receiver with the SMI algorithm and with or without IQ imbalance, as well as BER curves for different phase noise models

Amphiphilic core-cross-linked micelles functionalized with bis(4-methoxyphenyl)phenylphosphine as catalytic nanoreactors for biphasic hydroformylation

Core-cross-linked micelles (CCM) functionalized at the core with covalently linked bis(p-methoxyphenyl) phenylphosphine (BMOPPP) ligands have been synthesized by a three-step one-pot radical polymerization in emulsion, using the polymerization-induced self-assembly (PISA) strategy and reversible addition-fragmentation chain transfer (RAFT) as the controlling method. The CCM are obtained by chain extending in water poly(methacrylic acid-co-poly(ethylene oxide) methyl ether methacrylate) (P(MAA-co-PEOMA), degree of polymerization of 30, MAA/PEOMA units molar ratio of 50:50) synthesized in a first step by RAFT with a 95:5 M mixture of styrene and 4-[bis(p-methoxyphenyl)phosphino]styrene (BMOPPS) units. The resulting micelles exhibiting a core composed of P(S-co-BMOPPS) segments with a degree of polymerization of 300 are then crosslinked in a third step with a mixture of di(ethylene glycol) dimethacrylate (DEGDMA) and styrene. The resulting BMOPPP@CCM exhibit a narrow size distribution (PDI = 0.16) with an average diameter of 81 nm in water and swell in THF or by addition of toluene to the latex. The addition of [Rh(acac) (CO)2] to the toluene-swollen latex results in metal coordination to the phosphine ligands. 31P{1H} NMR spectroscopy shows that the Rh centers undergo rapid intraparticle phosphine ligand exchange. Application of these nanoreactors to the aqueous biphasic hydroformylation of 1-octene shows excellent activity and moderate catalyst leaching