Prospective Memory Predictions in Aging : Increased Overconfidence in Older Adults

Funding: This study was founded by a joint grant from the Swiss National Science Foundation (SNSF) and the Agence Nationale de Recherche (ANR; France). We thank Charlotte Caparaos, Sophie Consigny, Clara Delaissiaz and Pauline Lopez for assistance with data collection. Preparation of this manuscript was funded by a joint grant from the Swiss National Science Foundation (SNSF), the Agence Nationale de Recherche (ANR; France) to MK, CM, KS and CS. CM gratefully acknowledges the support of the Institut Universitaire de France.Peer reviewedPostprin

Casein haplotype structure in five Italian goat breeds

The aim of this work was to investigate the genetic structure of the casein gene cluster in 5 Italian goat breeds and to evaluate the haplotype variability within and among populations. A total of 430 goats from Vallesana, Roccaverano, Jonica, Garganica, and Maltese breeds were genotyped at alphas1-casein (CSN1S1), alphas2-casein, (CSN1S2), beta-casein (CSN2), and kappa-casein (CSN3) loci using several genomic techniques and milk protein analysis. Casein haplotype frequencies were estimated for each breed. Principal component analysis was carried out to highlight the relationship among breeds. Allele and haplotype distributions indicated considerable differences among breeds. The haplotype CSN1S1*F- CSN1S2*F-CSN3*D occurred in all breeds with frequencies >0.100 and was the most common haplotype in the Southern breeds. A high frequency of CSN1S1*0-CSN1S2*C-CSN3*A haplotype was found in Vallesana population (0.162). Principal component analysis clearly separated the Northern and Southern breeds by the first component. The variability of the caprine casein loci and variety of resulting haplotypes should be exploited in the future using specific breeding programs aiming to preserve biodiversity and to select goat genetic lines for specific protein production

Four-particle condensate in strongly coupled fermion systems

Four-particle correlations in fermion systems at finite temperatures are investigated with special attention to the formation of a condensate. Instead of the instability of the normal state with respect to the onset of pairing described by the Gorkov equation, a new equation is obtained which describes the onset of quartetting. Within a model calculation for symmetric nuclear matter, we find that below a critical density, the four-particle condensation (alpha-like quartetting) is favored over deuteron condensation (triplet pairing). This pairing-quartetting competition is expected to be a general feature of interacting fermion systems, such as the excition-biexciton system in excited semiconductors. Possible experimental consequences are pointed out.Comment: LaTeX, 11 pages, 2 figures, uses psfig.sty (included), to be published in Phys. Rev. Lett., tentatively scheduled for 13 April 1998 (Volume 80, Number 15

Les activités d'une salle de travaux pratiques informatisée

Utilisation des micro-ordinateurs dans des activités non directives en travaux pratiques de sciences physiques. L'expérimentation a commencé au printemps 1992 juste après l'aménagement des salles nouvellement construites. Les élèves avaient déjà été un peu initiés à l'outil depuis le début de la classe de seconde lors d'expériences de cours ou de travaux pratiques collectifs. Les années suivantes, les activités pourront être pratiquées tout au long de l'année. L'expérience a été faite avec trois classes de première S (jugées de niveau très moyen) durant trois séances de travaux pratiques. La première séance a été consacrée à une initiation à l'outil et les deux autres à l'étude des circuits dérivateurs. Des observations ont pu être faites. D'abord on a pu constater que la plupart des élèves arrivent plus ou moins au résultat (même au passage au circuit intégrateur) aidés en cela par la dynamique de la classe. La remarque essentielle concerne le manque d'aptitude des élèves à l'autonomie, sans doute occasionné par une formation préalable excessivement directive. On sent qu'ils n'osent pas prendre d'initiatives même dans le fonctionnement du logiciel, comme s'ils avaient peur de le détériorer. Aux nombreux collègues qui trouvent que la recherche-action sur l'ordinateur outil de laboratoire traîne en longueur et que le passage à l'acte se fait attendre, nous pouvons répondre que pour que ces techniques soient assimilables il faut qu'elles soient pratiquées par les élèves. Pour cela il faut d'abord que le matériel soit en quantité suffisante dans les collections des laboratoires, ensuite que les enseignants aient suffisamment d'imagination pour concevoir des situations qui ne se contentent pas de reproduire les démarches pédagogiques ancestrales. L'expérience du lycée de Manosque constitue dans ce domaine un modèle qui mérite d'être suivi.Use of computers for no-directing activities in laboratory of physical sciences

Policies to Regulate Distributed Data Exchange

This research is partially sponsored by the EPSRC grant EP/P011829/1, funded under the UK Engineering and Physical Sciences Council Human Dimensions of Cyber Security call (2016).Postprin

Detour and break optimising distance, a new perspective on transport and urbanism

International audienceFrom a discussion about the mathematical properties of metrics, we identify three fundamental characteristics of distance, which are optimality, detour and break. We then explore the implications of these properties for transport planning, urbanism and spatial planning. We state that distances contain the idea of optimum and that any distance is associated to a search for optimisation. Pedestrian movements obey this principle and sometimes depart from designed routes. Local sub-optimality conveyed by public transport maps has to be corrected by interventions on public space to relieve the load on central parts of networks. The second principle we state is that detour in distances is most often a means to optimise movement. Fast transport systems generates most of the detour observed in geographical spaces at regional scale. This is why detour has to be taken into account in regional transport policies. The third statement is that breaks in movement contribute to optimising distances. Benches, cafés, pieces of art, railway stations are examples of the urban break. These facilities of break represent an urban paradox: they organise the possibility of a break, of a waste of time in a trip, and they also contribute to optimising distances in a wider network. In that sense break should be considered as a relevant principle for the design of urban space in order to support a pedestrian oriented urban form

Are block copolymer worms more effective Pickering emulsifiers than block copolymer spheres?

RAFT-mediated polymerisation-induced self-assembly (PISA) is used to prepare six types of amphiphilic block copolymer nanoparticles which were subsequently evaluated as putative Pickering emulsifiers for the stabilisation of n-dodecane-in-water emulsions. It was found that linear poly(glycerol monomethacrylate)–poly(2-hydroxypropyl methacrylate) (PGMA–PHPMA) diblock copolymer spheres and worms do not survive the high shear homogenisation conditions used for emulsification. Stable emulsions are obtained, but the copolymer acts as a polymeric surfactant; individual chains rather than particles are adsorbed at the oil–water interface. Particle dissociation during emulsification is attributed to the weakly hydrophobic character of the PHPMA block. Covalent stabilisation of these copolymer spheres or worms can be readily achieved by addition of ethylene glycol dimethacrylate (EGDMA) during the PISA synthesis. TEM studies confirm that the resulting cross-linked spherical or worm-like nanoparticles survive emulsification and produce genuine Pickering emulsions. Alternatively, stabilisation can be achieved by either replacing or supplementing the PHPMA block with the more hydrophobic poly(benzyl methacrylate) (PBzMA). The resulting linear spheres or worms also survive emulsification and produce stable n-dodecane-in-water Pickering emulsions. The intrinsic advantages of anisotropic worms over isotropic spheres for the preparation of Pickering emulsions are highlighted. The former particles are more strongly adsorbed at similar efficiencies compared to spheres and also enable smaller oil droplets to be produced for a given copolymer concentration. The scalable nature of PISA formulations augurs well for potential applications of anisotropic block copolymer nanoparticles as Pickering emulsifiers

Preparation of double emulsions using hybrid polymer/silica particles: New pickering emulsifiers with adjustable surface wettability

A facile route for the preparation of water-in-oil-in-water (w/o/w) double emulsions is described for three model oils, namely, n-dodecane, isopropyl myristate, and isononyl isononanoate, using fumed silica particles coated with poly(ethylene imine) (PEI). The surface wettability of such hybrid PEI/silica particles can be systematically adjusted by (i) increasing the adsorbed amount of PEI and (ii) addition of 1-undecanal to the oil phase prior to homogenization. In the absence of this long-chain aldehyde, PEI/silica hybrid particles (PEI/silica mass ratio = 0.50) produce o/w Pickering emulsions in all cases. In the presence of 1-undecanal, this reagent reacts with the primary and secondary amine groups on the PEI chains via Schiff base chemistry, which can render the PEI/silica hybrid particles sufficiently hydrophobic to stabilize w/o Pickering emulsions at 20 °C. Gas chromatography, 1H NMR and X-ray photoelectron spectroscopy provide compelling experimental evidence for this in situ surface reaction, while a significant increase in the water contact angle indicates markedly greater hydrophobic character for the PEI/silica hybrid particles. However, when PEI/silica hybrid particles are prepared using a relatively low adsorbed amount of PEI (PEI/silica mass ratio = 0.075) only o/w Pickering emulsions are obtained, since the extent of surface modification achieved using this Schiff base chemistry is insufficient. Fluorescence microscopy and laser diffraction studies confirm that highly stable w/o/w double emulsions can be achieved for all three model oils. This is achieved by first homogenizing the relatively hydrophobic PEI/silica hybrid particles (PEI/silica mass ratio = 0.50) with an oil containing 3% 1-undecanal to form an initial w/o emulsion, followed by further homogenization using an aqueous dispersion of relatively hydrophilic PEI/silica particles (PEI/silica mass ratio = 0.075). Dye release from the internal aqueous cores into the aqueous continuous phase was monitored by visible absorption spectroscopy. These studies indicate immediate loss of 12-18% dye during the high speed homogenization that is required for double emulsion formation, but no further dye release is observed at 20 °C for at least 15 days thereafter