Possibilities and problems of using pupillary reflex for subconscious detection of consumer preferences

The article describes the possibilities of using the pupillary light reflex for subconscious ascertainment of consumer preferences also in technical, industrial sectors. It describes the essence and use of pupillometry in marketing, types of pupillometry, practical suggestions as well as the prerequisites for future use in marketing. It suggests the procedures of an experiment with the use of an eye camera with an integrated pupillometer, and it points out to selected practical problems which must be eliminated during the experiments. If we wish to achieve growth of the industry the first necessary step is clear focus on the customer and on a user-friendly program of communication with customers and potential customers

Cones, pringles, and grain boundary landscapes in graphene topology

A polycrystalline graphene consists of perfect domains tilted at angle {\alpha} to each other and separated by the grain boundaries (GB). These nearly one-dimensional regions consist in turn of elementary topological defects, 5-pentagons and 7-heptagons, often paired up into 5-7 dislocations. Energy G({\alpha}) of GB computed for all range 0<={\alpha}<=Pi/3, shows a slightly asymmetric behavior, reaching ~5 eV/nm in the middle, where the 5's and 7's qualitatively reorganize in transition from nearly armchair to zigzag interfaces. Analysis shows that 2-dimensional nature permits the off-plane relaxation, unavailable in 3-dimensional materials, qualitatively reducing the energy of defects on one hand while forming stable 3D-landsapes on the other. Interestingly, while the GB display small off-plane elevation, the random distributions of 5's and 7's create roughness which scales inversely with defect concentration, h ~ n^(-1/2)Comment: 9 pages, 4 figure

A survey on parallel and distributed Multi-Agent Systems

International audienceSimulation has become an indispensable tool for researchers to explore systems without having recourse to real experiments. Depending on the characteristics of the modeled system, methods used to represent the system may vary. Multi-agent systems are, thus, often used to model and simulate complex systems. Whatever modeling type used, increasing the size and the precision of the model increases the amount of computation, requiring the use of parallel systems when it becomes too large. In this paper, we focus on parallel platforms that support multi-agent simulations. Our contribution is a survey on existing platforms and their evaluation in the context of high performance computing. We present a qualitative analysis, mainly based on platform properties, then a performance comparison using the same agent model implemented on each platform

Grain Boundaries in Graphene on SiC(0001ˉ\bar{1}) Substrate

Grain boundaries in epitaxial graphene on the SiC(000$\bar{1}$) substrate are studied using scanning tunneling microscopy and spectroscopy. All investigated small-angle grain boundaries show pronounced out-of-plane buckling induced by the strain fields of constituent dislocations. The ensemble of observations allows to determine the critical misorientation angle of buckling transition $\theta_c = 19 \pm~2^\circ$. Periodic structures are found among the flat large-angle grain boundaries. In particular, the observed $\theta = 33\pm2^\circ$ highly ordered grain boundary is assigned to the previously proposed lowest formation energy structural motif composed of a continuous chain of edge-sharing alternating pentagons and heptagons. This periodic grain boundary defect is predicted to exhibit strong valley filtering of charge carriers thus promising the practical realization of all-electric valleytronic devices

Ferromagnetism in graphene nanoribbons: split versus oxidative unzipped ribbons

Two types of graphene nanoribbons: (a) potassium-split graphene nanoribbons (GNRs), and (b) oxidative unzipped and chemically converted graphene nanoribbons (CCGNRs) were investigated for their magnetic properties using the combination of static magnetization and electron spin resonance measurements. The two types of ribbons possess remarkably different magnetic properties. While the low temperature ferromagnet-like feature is observed in both types of ribbons, such room temperature feature persists only in potassium-split ribbons. The GNRs show negative exchange bias, but the CCGNRs exhibit a 'positive exchange bias'. Electron spin resonance measurements infer that the carbon related defects may responsible for the observed magnetic behaviour in both types of ribbons. Furthermore, proton hyperfine coupling strength has been obtained from hyperfine sublevel correlation experiments performed on the GNRs. Electron spin resonance provides no indications for the presence of potassium (cluster) related signals, emphasizing the intrinsic magnetic nature of the ribbons. Our combined experimental results may infer the coexistence of ferromagnetic clusters with anti-ferromagnetic regions leading to disordered magnetic phase. We discuss the origin of the observed contrast in the magnetic behaviours of these two types of ribbons

sp-Electron Magnetic Clusters with a Large Spin in Graphene

Motivated by recent experimental data (Sepioni, M. et al. Phys. Rev. Lett. 2010, 105, 207205), we have studied the possibility of forming magnetic clusters with spin S> 1/2 on graphene by adsorption of hydrogen atoms or hydroxyl groups. Migration of hydrogen atoms and hydroxyl groups on the surface of graphene during the delamination of HOPG led to the formation of seven-atom or seven-OH-group clusters with S=5/2 that were of a special interest. The coincidence of symmetry of the clusters with the graphene lattice strengthens the stability of the cluster. For (OH)7 clusters that were situated greater than 3 nm from one another, the reconstruction barrier to a nonmagnetic configuration was approximately 0.4 eV, whereas for H7 clusters, there was no barrier and the high-spin state was unstable. Stability of the high-spin clusters increased if they were formed on top of ripples. Exchange interactions between the clusters were studied and we have shown that the ferromagnetic state is improbable. The role of the chemical composition of the solvent used for the delamination of graphite is discussed.Comment: 22 pages, 1 table, 4 figures. Minor changes, few refs added. Accepted to ACS Nan

Mapping cortical brain asymmetry in 17,141 healthy individuals worldwide via the ENIGMA Consortium.

Hemispheric asymmetry is a cardinal feature of human brain organization. Altered brain asymmetry has also been linked to some cognitive and neuropsychiatric disorders. Here, the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Consortium presents the largest-ever analysis of cerebral cortical asymmetry and its variability across individuals. Cortical thickness and surface area were assessed in MRI scans of 17,141 healthy individuals from 99 datasets worldwide. Results revealed widespread asymmetries at both hemispheric and regional levels, with a generally thicker cortex but smaller surface area in the left hemisphere relative to the right. Regionally, asymmetries of cortical thickness and/or surface area were found in the inferior frontal gyrus, transverse temporal gyrus, parahippocampal gyrus, and entorhinal cortex. These regions are involved in lateralized functions, including language and visuospatial processing. In addition to population-level asymmetries, variability in brain asymmetry was related to sex, age, and intracranial volume. Interestingly, we did not find significant associations between asymmetries and handedness. Finally, with two independent pedigree datasets (n = 1,443 and 1,113, respectively), we found several asymmetries showing significant, replicable heritability. The structural asymmetries identified and their variabilities and heritability provide a reference resource for future studies on the genetic basis of brain asymmetry and altered laterality in cognitive, neurological, and psychiatric disorders