Rotational 3D Printing of Sensor Devices using Reactive Ink Chemistries

This paper charts progress in three key areas of a project supported by both UK government and UK industry to manufacture novel sensor devices using rotary 3D printing technology and innovative ink chemistries; (1) the development of an STL file slicing algorithm that returns constant Z height 2D contour data at a resolution that matches the given print head setup, allowing digital images to be generated of the correct size without the need for scaling; (2) the development of image transformation algorithms which allow images to be printed at higher resolutions using tilted print heads and; (3) the formulation of multi part reaction inks which combine and react on the substrate to form solid material layers with a finite thickness. A Direct Light Projection (DLP) technique demonstrated the robustness of the slice data by constructing fine detailed three dimensional test pieces which were comparable to identical parts built in an identical way from slice data obtained using commercial software. Material systems currently under investigation include plaster, stiff polyamides and epoxy polymers and conductive metallic’s. Early experimental results show conductivities of silver approaching 1.42x105 Siemens/m.Mechanical Engineerin

Modelling Social Structures and Hierarchies in Language Evolution

Language evolution might have preferred certain prior social configurations over others. Experiments conducted with models of different social structures (varying subgroup interactions and the role of a dominant interlocutor) suggest that having isolated agent groups rather than an interconnected agent is more advantageous for the emergence of a social communication system. Distinctive groups that are closely connected by communication yield systems less like natural language than fully isolated groups inhabiting the same world. Furthermore, the addition of a dominant male who is asymmetrically favoured as a hearer, and equally likely to be a speaker has no positive influence on the disjoint groups.Comment: 14 pages, 3 figures, 1 table. In proceedings of AI-2010, The Thirtieth SGAI International Conference on Innovative Techniques and Applications of Artificial Intelligence, Cambridge, England, UK, 14-16 December 201

Effect of spin orbit scattering on the magnetic and superconducting properties of nearly ferromagnetic metals: application to granular Pt

We calculate the effect of scattering on the static, exchange enhanced, spin susceptibility and show that in particular spin orbit scattering leads to a reduction of the giant moments and spin glass freezing temperature due to dilute magnetic impurities. The harmful spin fluctuation contribution to the intra-grain pairing interaction is strongly reduced opening the way for BCS superconductivity. We are thus able to explain the superconducting and magnetic properties recently observed in granular Pt as due to scattering effects in single small grains.Comment: 9 pages 3 figures, accepted for publication in Phys. Rev. Letter

Infrared study of spin crossover Fe-picolylamine complex

Infrared (IR) absorption spectroscopy has been used to probe the evolution of microscopic vibrational states upon the temperature- and photo-induced spin crossovers in [Fe(2-picolylamine)3]Cl2EtOH (Fe-pic). To overcome the small sizes and the strong IR absorption of the crystal samples used, an IR synchrotron radiation source and an IR microscope have been used. The obtained IR spectra of Fe-pic show large changes between high-spin and low-spin states for both the temperature- and the photo- induced spin crossovers. Although the spectra in the temperature- and photo-induced high-spin states are relatively similar to each other, they show distinct differences below 750 cm-1. This demonstrates that the photo-induced high-spin state involves microscopically different characters from those of the temperature-induced high-spin state. The results are discussed in terms of local pressure and structural deformations within the picolylamine ligands, and in terms of their possible relevance to the development of macroscopic photo-induced phase in Fe-pic.Comment: 6 pages (text) and 6 figures,submitted to J. Phys. Soc. Jp

Adolescents\u27 Behavior in the Presence of Interparental Hostility: Developmental and Emotion Regulatory Influences

Within-family covariation between interparental hostility and adolescent behavior across three interactions over a 2-year period was explored in a sample that included 37 typical adolescents and 35 adolescents recently hospitalized for psychiatric difficulties. More interparental hostility across the three interactions was associated with more adolescent hostility and more positive engagement (at a trend level) regardless of psychiatric background. Parent-to-child hostility in each interaction mediated the link for adolescent hostility but not for positive adolescent engagement. Emotion regulation capacities and age were linked to variability in adolescents\u27 behavior in the presence of interparental conflict. In interactions with more interparental hostility, adolescents with greater capacity to tolerate negative affect were more likely to show increased positive engagement, and adolescents who were better able to modulate their emotional expression were less likely to show increased hostility. Covariation between interparental and adolescent hostility across the three family interactions decreased as the adolescent aged. These findings are consistent with the theory that exposure to inter-parental hostility is emotionally disequilibrating, and that adolescent responses may reflect differences in emotion regulation and other developmentally based capacities. Gender and variations across families in overall levels of hostile parenting were also linked with adolescent behavior in the presence of interparental hostility

Adolescents\u27 Behavior in the Presence of Interparental Hostility: Developmental and Emotion Regulatory Influences

Within-family covariation between interparental hostility and adolescent behavior across three interactions over a 2-year period was explored in a sample that included 37 typical adolescents and 35 adolescents recently hospitalized for psychiatric difficulties. More interparental hostility across the three interactions was associated with more adolescent hostility and more positive engagement (at a trend level) regardless of psychiatric background. Parent-to-child hostility in each interaction mediated the link for adolescent hostility but not for positive adolescent engagement. Emotion regulation capacities and age were linked to variability in adolescents\u27 behavior in the presence of interparental conflict. In interactions with more interparental hostility, adolescents with greater capacity to tolerate negative affect were more likely to show increased positive engagement, and adolescents who were better able to modulate their emotional expression were less likely to show increased hostility. Covariation between interparental and adolescent hostility across the three family interactions decreased as the adolescent aged. These findings are consistent with the theory that exposure to inter-parental hostility is emotionally disequilibrating, and that adolescent responses may reflect differences in emotion regulation and other developmentally based capacities. Gender and variations across families in overall levels of hostile parenting were also linked with adolescent behavior in the presence of interparental hostility