Continuous Interaction with a Virtual Human

Attentive Speaking and Active Listening require that a Virtual Human be capable of simultaneous perception/interpretation and production of communicative behavior. A Virtual Human should be able to signal its attitude and attention while it is listening to its interaction partner, and be able to attend to its interaction partner while it is speaking – and modify its communicative behavior on-the-fly based on what it perceives from its partner. This report presents the results of a four week summer project that was part of eNTERFACE’10. The project resulted in progress on several aspects of continuous interaction such as scheduling and interrupting multimodal behavior, automatic classification of listener responses, generation of response eliciting behavior, and models for appropriate reactions to listener responses. A pilot user study was conducted with ten participants. In addition, the project yielded a number of deliverables that are released for public access

The Effect of Wealth Shocks on Loss Aversion: Behavior and Neural Correlates

Kahneman and Tversky (1979) first demonstrated that when individuals decide whether or not to accept a gamble, potential losses receive more weight than possible gains in the decision. This phenomenon is referred to as loss aversion. We investigated how loss aversion in risky financial decisions is influenced by sudden changes to wealth, employing both behavioral and neurobiological measures. We implemented an fMRI experimental paradigm, based on that employed by Tom et al. (2007). There are two treatments, called RANDOM and CONTINGENT. In RANDOM, the baseline setting, the changes to wealth, referred to as wealth shocks in economics, are independent of the actual choices participants make. Under CONTINGENT, we induce the belief that the changes in income are a consequence of subjects' own decisions. The magnitudes and sequence of the shocks to wealth are identical between the CONTINGENT and RANDOM treatments. We investigated whether more loss aversion existed in one treatment than another. The behavioral results showed significantly greater loss aversion in CONTINGENT compared to RANDOM after a negative wealth shock. No differences were observed in the response to positive shocks. The fMRI results revealed a neural loss aversion network, comprising the bilateral striatum, amygdala and dorsal anterior cingulate cortex that was common to the CONTINGENT and RANDOM tasks. However, the ventral prefrontal cortex, primary somatosensory cortex and superior occipital cortex, showed greater activation in response to a negative change in wealth due to individual's own decisions than when the change was exogenous. These results indicate that striatum activation correlates with loss aversion independently of the source of the shock, and that the ventral prefrontal cortex (vPFC) codes the experimental manipulation of agency in one's actions influencing loss aversion

Predominant Stable MAPbI₃ Films Deposited via Chemical Vapor Deposition: Stability Studies in Illuminated and Darkened States Coupled with Temperature under an Open-Air Atmosphere

Although the use of perovskite materials in solar cells has drawn a tremendous amount of attention because of rewarding power-conversion efficiency of 22.1%, concerns persist that poor stability will hinder the commercial viability of perovskite-based photovoltaic devices. Chemical vapor deposition (CVD) is the most suitable technology for commercialization and could potentially provide a future perspective for stable and efficient perovskite-based electronic devices. Until now, systematic investigation has addressed neither the preparation nor the intrinsic stability of these materials under both dark and illuminated conditions given the high humidity of perovskite films deposited by CVD. In the present study, we investigated the stability of perovskite films under dark and illuminated conditions coupled with temperature under an open-air atmosphere via the tuning of various deposition parameters. CVD-deposited MAPbI₃ films with no additives showed structural and optical properties at a predominant level of stability for ∼2000 h in dark and ∼1000 h under ambient room lighting, which achieved a significantly higher level of stability than that  of either solution-processed perovskite films with or without additives, or for composites with polymers. The outstanding stability of CVD-deposited MAPbI₃ films is attributed to their large grain sizes with high levels of crystalline quality and chemical purity

The Effect of Wealth Shocks on Loss Aversion: Behavior and Neural Correlates

Kahneman and Tversky (1979) first demonstrated that when individuals decide whether or not to accept a gamble, potential losses receive more weight than possible gains in the decision. This phenomenon is referred to as loss aversion. We investigated how loss aversion in risky financial decisions is influenced by sudden changes to wealth, employing both behavioral and neurobiological measures. We implemented an fMRI experimental paradigm, based on that employed by Tom et al. (2007). There are two treatments, called RANDOM and CONTINGENT. In RANDOM, the baseline setting, the changes to wealth, referred to as wealth shocks in economics, are independent of the actual choices participants make. Under CONTINGENT, we induce the belief that the changes in income are a consequence of subjects' own decisions. The magnitudes and sequence of the shocks to wealth are identical between the CONTINGENT and RANDOM treatments. We investigated whether more loss aversion existed in one treatment than another. The behavioral results showed significantly greater loss aversion in CONTINGENT compared to RANDOM after a negative wealth shock. No differences were observed in the response to positive shocks. The fMRI results revealed a neural loss aversion network, comprising the bilateral striatum, amygdala and dorsal anterior cingulate cortex that was common to the CONTINGENT and RANDOM tasks. However, the ventral prefrontal cortex, primary somatosensory cortex and superior occipital cortex, showed greater activation in response to a negative change in wealth due to individual's own decisions than when the change was exogenous. These results indicate that striatum activation correlates with loss aversion independently of the source of the shock, and that the ventral prefrontal cortex (vPFC) codes the experimental manipulation of agency in one's actions influencing loss aversion.University Grants Commission (UGC), Government of India, Centre of Excellence Grant; Comision Nacional de Investigacion Cientifica y Tecnologica de Chile (Conicyt) through Fondo Nacional de Desarrollo Cientifico y Tecnologico, Fondecyt Regular [1171313, 1171320]; BMBF [01DQ13004]; Proyectos de Investigacion Interdisciplinaria, Vicerrectoria de Investigacion (VRI), Pontificia Universidad Catolica de Chile [15/2013]; CONICYT-PCHA/Magister Nacional [2014-22140196]; CONICYT-PIA Anillo [ACT1416, ACT1414]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Polarization-Sensitive Photodetector Using Patterned Perovskite Single-Crystalline Thin Films

Hybrid organic–inorganic perovskite single crystals, compared with their polycrystalline counterparts in thin films, are free from grain boundaries and have fewer defects, and therefore are promising in high-performance optoelectronic devices. Recently, the crystal-structure anisotropy in perovskites has been utilized to achieve polarization-sensitive photodetectors. Here, it is shown that under 532 nm linearly polarized illumination, although MAPbBr3 (MA=CH3NH3+1) single crystals possess weak in-plane anisotropy, nanogratings made on the crystal surface lead to high polarization photodetection sensitivity of ≈2.2 comparable with that of the isotropic perovskite crystals and nanowires, while enhancing both the photodetection responsivity and external quantum efficiency. The surface nanopattern induced polarization sensitivity may find interesting applications in future optoelectronic devices