33 research outputs found
Social chemosignals, but not common odors valence, modulate approach/avoidance response tendencies
No full textActions of basic motivational tendency are differentially influenced by stimulus valence: positive stimuli are approached and negative stimuli are avoided. This affective-motor biasis stronger with social-informative facial expression. In 3 experiments, we determined whether common odors or social chemosignals (body odors from an unknown individual) modulate this basic approach-avoidance bias towards human facial expressions. Within an approach-avoidance task (AAT), participants responded by pulling towards or pushing away a joystick in response to happy, angry, and neutral facial expressions paired with no odor (Study 1, n=10), or neutral, pleasant, and unpleasant common odors (Study 2; n=20), or perceptually masked social chemosignals (Study 3; n=25). In
Study 1, we replicated that individuals both approach happy faces and avoid angry faces more quickly. In Study 2, odors – independent of valence – removed the established approach and avoidance effects, which suggests that odors acted as distractors. In Study 3, an initial discrimination test determined that the body odor masked with an odor mixture of neutral valence was perceptually indiscriminable from the mixture itself. Preliminary analyses of the ATT result suggests that only when faces were paired with the masked social chemosignal were participants
faster at approaching happy faces and avoiding angry faces. As in Study 2, when paired with the masker alone, the approachavoidance effect was eliminated. These findings indicate that social chemosignals, but not common odors, are able to induce differential behavioral responses to emotional stimuli. Furthermore, these social chemosignal-dependent effects occur outside perceptual awareness. Acknowledgements: Supported by
the Knut and Alice Wallenberg foundation (KAW 2012.0141) awarded to JNL. FCOI Disclosure: Non
[Seitelberger's infantile neuroaxonal dystrophy: anatomoclinical study of a sibling group]
No full text14-bit 2.2-MS/s sigma-delta ADC's
No full textThis paper presents the design and test results of a fourth-order and sixth-order 14-bit 2.2-MS/s sigma-delta analog-to-digital converter (ADC). The analog modulator and digital decimator sections were implemented in a 0.35 μm CMOS double-poly triple-level metal 3.3-V process. The design objective for these ADC's was to achieve 85 dB signal-to-noise distortion ratio (SNDR) with less than 200 mW power dissipation. Both modulators employ a cascade sigma-delta topology. The fourth-order modulator consists of two cascaded second-order stages which include 1-bit and 5-bit quantizers, respectively. The sixth-order modulator has a 2-2-2 cascade structure and 1-bit quantizer at the end of each stage. An oversampling ratio of 24 was selected to give the best SNDR and power consumption with realizable gain-matching requirements between the analog and digital section
Implicit regularization for optimal sparse recovery
No full textWe investigate implicit regularization schemes for gradient descent methods applied to unpenalized least squares regression to solve the problem of reconstructing a sparse signal from an underdetermined system of linear measurements under the restricted isometry assumption. For a given parametrization yielding a non-convex optimization problem, we show that prescribed choices of initialization, step size and stopping time yield a statistically and computationally optimal algorithm that achieves the minimax rate with the same cost required to read the data up to poly-logarithmic factors. Beyond minimax optimality, we show that our algorithm adapts to instance difficulty and yields a dimension-independent rate when the signal-to-noise ratio is high enough. Key to the computational efficiency of our method is an increasing step size scheme that adapts to refined estimates of the true solution. We validate our findings with numerical experiments and compare our algorithm against explicit penalization. Going from hard instances to easy ones, our algorithm is seen to undergo a phase transition, eventually matching least squares with an oracle knowledge of the true support
Decentralized cooperative stochastic bandits
No full textWe study a decentralized cooperative stochastic multi-armed bandit problem with K arms on a network of N agents. In our model, the reward distribution of each arm is the same for each agent and rewards are drawn independently across agents and time steps. In each round, each agent chooses an arm to play and subsequently sends a message to her neighbors. The goal is to minimize the overall regret of the entire network. We design a fully decentralized algorithm that uses an accelerated consensus procedure to compute (delayed) estimates of the average of rewards obtained by all the agents for each arm, and then uses an upper confidence bound (UCB) algorithm that accounts for the delay and error of the estimates. We analyze the regret of our algorithm and also provide a lower bound. The regret is bounded by the optimal centralized regret plus a natural and simple term depending on the spectral gap of the communication matrix. Our algorithm is simpler to analyze than those proposed in prior work and it achieves better regret bounds, while requiring less information about the underlying network. It also performs better empirically
L'arte italiana nel quattrocento .
No full textTranslation of v. 1 of Histoire de l'art pendant la renaissance."Dono agli abbonati del Corriere della sera."Mode of access: Internet
Costruzione di strumenti di micrografia : catalogo illustrato descrittivo n° 12, 1905
No full text1 vol. (99 p.) : ill. ; 27 c
A testing facility for AO on-sky demonstrations at the Copernico's telescope within the ADONI framework
No full textIn the context of ADONI - the ADaptive Optics National laboratory of INAF – we are arranging for a facility, accessible to the AO community, in which visiting multi-purpose instrumentation, e.g. systems and prototypes of innovative AO concepts, may be directly tested on sky. The facility is located at the 182cm Copernico telescope in Asiago, the largest telescope in Italy, at its Coudè focus, for which refurbishment activities are carried out, given that this focus was initially foreseen in the design, but never implemented and used till today. The facility hosts a laboratory where specialized visiting AO instrumentation may be properly accommodated on an optical bench for on-sky demonstrations. We present the current status of the facility, describing the opto-mechanical design implemented at the telescope that allows to redirect the light toward the Coudè focus, the tests on the opto-mechanics carried on for stability verification, the integration of the optical and mechanical components within the preexisting structure
A testing facility for AO on-sky demonstrations at the Copernico's Telescope within the Adoni framework
No full textIn the context of Adoni-the ADaptive Optics National laboratory of INAF-we are arranging for a facility, accessible to the AO community, in which visiting multi-purpose instrumentation, e.g. Systems and prototypes of innovative AO concepts, may be directly tested on sky. The facility is located at the 182cm Copernico telescope in Asiago, the largest telescope in Italy, at its Coudè focus, for which refurbishment activities are carried out, given that this focus was initially foreseen in the design, but never implemented and used till today. The facility hosts a laboratory where specialized visiting AO instrumentation may be properly accommodated on an optical bench for on-sky demonstrations. We present the current status of the facility, describing the opto-mechanical design implemented at the telescope that allows to redirect the light toward the Coudè focus, the tests on the opto-mechanics carried on for stability verification, the integration of the optical and mechanical components within the preexisting structure
