Application of Magnetoencephalography and spectro-temporal analysis methods to the study of "real life" auditory scenes perception

In this study brain's behavior during a typical cocktail party situation has been investigated. To this purpose, stereo and mono complex auditory scenes composed of a mixture of human voice and natural environmental sounds were used for the stimulation; as experimental task, subjects were asked to focus their attention on the voice or the background noise. Thus, the experimental conditions were: mono attention to voice (mav), mono attention to environment (mae), stereo attention to voice (sav), stereo attention to environment (sae). Magnetoencephalography (MEG) has been used as neuroimaging modality for its high temporal resolution and its property to reflect dynamics of neural activity directly. MEG data they were checked for physiological and electronics artifacts by combining artifacts correction and artifacts rejection strategies. They were first cleaned from artifacts deriving from eyes blinks, eyes movements and heart activity by using ICA; then, a visual inspection of the data trial by trial was performed in order to remove trials contaminated with artifacts caused by electronics or head movements. Three main analysis of artifacts-free data were performed: an analysis of the time course and topographies of the evoked fields at the sensor level, an analysis of the sources underlying the observed evoked fields, and a time-frequency analysis of the MEG signal at the sensor level. For each condition of each subject in the study, evoked fields were obtained by averaging all trials left after the artifact rejection procedure; they were baseline corrected with respect to a prestimulus period, transformed to planar gradients, and pooled across subjects to obtain grand-averaged planar evoked fields. For a raw assessment of auditory activity, time courses of sensors located over the auditory areas were averaged separately for each brain hemisphere. Consistent with the typical magnetic auditory evoked response, signals in the auditory channels presented two transient responses, peaked respectively around 50 ms (M50) and 100 ms (M100) after stimulus onset, followed by a response sustained over several hundreds of milliseconds. To localize the current sources underlying the evoked fields without a priori assumptions about their number and location, a cortically constrained depth-weighted noise-normalized minimum norm estimate (MNE) was performed.In order to obtain statistical maps of the main and differential effects, single trial data from each subject and each experimental condition were projected to the cortex source space. Main and dierential effects in a given time latency were evaluated via t-tests at each vertex of the source space. MNE localized sources of activity in left and right auditory cortex, though for all conditions the activation was stronger in the right hemisphere. The multi-subject statistical fixed-effects analysis revealed no signicant differential effects between sav and sae conditions. By contrast, statistical comparison of mav and mae conditions in the interval 150 ms - 360 ms was able to identify one significant region (pmae). The sensor-level analysis of the induced response was performed separately for two frequency ranges: 4-30 Hz and 30 - 100 Hz. Time-frequency representations (TFRs) of signal power were computed for each trial and averaged. The obtained TFRs were then averaged across subjects. In order to assess the phase relation of the observed change in power to the stimulus onset, the inter-trial coherence was computed

Beyond the Suffering of Being: Desire in Giacomo Leopardi and Samuel Beckett

In this dissertation, I question critical approaches that argue for Giacomo Leopardi’s and Samuel Beckett’s pessimism and nihilism. Beckett quotes Leopardi when discussing the removal of desire in his monograph Proust, a context that has spurred pessimist and nihilist readings, whether the focus has been on one writer, the other, or both. I argue that the inappropriateness of the pessimist and nihilist label is, on the contrary, specifically exposed through the role of desire in the two thinkers. After tracing the notion of desire as it developed from Leopardi to key twentieth-century thinkers, I illustrate how, in contrast to the Greek concept of ataraxia as a form of ablation of desire, the desire of and for the Other is central in the two authors’ oeuvres. That is, while the two writers’ attempt to reach the respective existential cores of Beckettian “suffering of being” and Leopardian “souffrance” might seem to point towards the celebrated nothingness of their existential quest, closer examination reveals that the attempt to still desire common to both authors is frustrated and outdone by a combative desire that pervades their later work. Hence, while the desire to cease desiring is at the philosophical kernel of both authors’ oeuvre, it also draws attention to and exacerbates the inextinguishable quality of desire. Looking at Leopardi’s later poetry in the ciclo d’Aspasia, including the last poem “La Ginestra, o il fiore del deserto,” and examining Beckett’s plays Endgame, Happy Days, Krapp’s Last Tape and Not I, I argue that desire in Leopardi and Beckett could be read as lying at the cusp between Jacques Lacan’s and Emmanuel Levinas’ theories, a desire that both splits the subject (and is thus based on lack) as much as it moulds the subject when called to address the Other (inspiring what Levinas terms ‘infinity’ as opposed to ‘totality,’ an infinity pitted against the nothingness crucial to pessimist and nihilist readings). The centrality of desire in Leopardi and Beckett also comes close to the Lacanian desire-as-paradox, a desire that is lodged at the heart of Leopardi’s and Beckett’s dianoetic laugh and held to be expressive of their particularly dark, but elevating, humour

Beyond the Suffering of Being: Desire in Giacomo Leopardi and Samuel Beckett

This book challenges critical approaches that argue for Giacomo Leopardi’s and Samuel Beckett’s pessimism and nihilism. Such approaches stem from the quotation of Leopardi in Beckett’s monograph Proust, as part of a discussion about the removal of desire. Nonetheless, in contrast to ataraxia as a form of ablation of desire, the desire of and for the Other is here presented as central in the two authors’ oeuvres. Desire in Leopardi and Beckett is read as lying at the cusp between the theories of Jacques Lacan and Emmanuel Levinas, a desire that splits as much as it moulds the subject when called to address the Other (inspiring what Levinas terms ‘infinity’ as opposed to ‘totality,’ an infinity pitted against the nothingness crucial to pessimist and nihilist readings)

Gibrat's Law and quantile regressions : an application to firm growth

The nexus between firm growth, size and age in U.S. manufacturing is examined through the lens of quantile regression models. This methodology allows us to overcome serious shortcomings entailed by linear regression models employed by much of the existing literature, unveiling a number of important properties. Size pushes both low and high performing firms towards the median rate of growth, while age is never advantageous, and more so as firms are relatively small and grow faster. These findings support theoretical generalizations of Gibrat's law that allow size to affect the variance of the growth process, but not its mean (Cordoba, 2008)

Extended Identification of Mechanical Parameters and Boundary Conditions by Digital Image Correlation

Abstract This paper represents a further contribution to the study of identification procedures for material mechanics resting on kinematic measurements provided by 2D Digital Image Correlation (DIC) at the microscale. Reference is made to non-conventional experiments on adhesively bonded assemblies industrially manufactured for aerospace applications. For calibration purposes a local approach is considered under plane stress conditions, focusing on a small sub-domain on the sample surface, in which mixed mode debonding is monitored. As a novelty, both the (cohesive) mechanical parameters of the interface and the actual boundary conditions prescribed at different time instants during the test are considered as unknowns to be estimated on the basis of full-field data. In this way, data smoothing and parameter identification procedures, so far usually performed in a sequence, are tackled simultaneously in a coupled framework. Since the inverse problem generalized as mentioned above turns out to be severely ill-posed, suitable regularizing provisions are applied, concerning the a priori regularity of (kinematic) displacement fields, from which boundary data are sampled, and the equilibrium (Neumann) conditions along the cracked part of the interface

Chiesa e web: il valore della dimensione digitale nella chiesa e la pandemia

The global pandemic has produced rules that impose suffering on religions, which must now reconsider their social role. This entails the need to examine the rules of coexistence within societies, where the COVID-19 phenomenon raises existential and religious questions. We need to look at the condition of the state of religious freedom, referring – in the European context – to globalisation in a climate of restriction of personal, social, and religious freedom. This complexity has underlined the role of states and delimited competences regarding relations with religions. Because building relationships with communities and associations where religious freedom is expressed is fundamental, believers are therefore bearers of specific interests. This particular situation calls for a new function for religions, focused on the value of the person, which can lead to a common identity and guarantee of “those values of social and community integration that seem particularly discovered today”. Today, religious confessions not only create a qualifying moment in the European process, but they act concretely, asking the European institutions to protect religious interests because these are an expression of values at the basis of civil coexistence. Gradually, dialogue becomes an instrument that is used juridically as part of the legislative construction through the production of appropriate programs. In the face of the challenges and needs resulting from social and international coexistence, religions must become part of the democratic process without forgetting and betraying the authenticity of their religious message and, at the same time, without conditioning or mortgaging the development of democracy

An exact approach to the dynamics of locally-resonant beams

Abstract This paper presents an exact analytical approach to calculate the dynamic response of elastic beams with periodically-attached resonators, generally referred to as locally-resonant beams. Showing that a typical resonator is equivalent to an external constraint, whose reaction force on the beam depends on the deflection of the application point through a pertinent frequency-dependent stiffness, the beam-resonators coupled system is handled using only the beam motion equation, with Dirac's deltas modelling the shear-force discontinuities associated with the reaction forces of the resonators. This is the basis to tackle the dynamics of infinite as well as finite beams, the first by a transfer matrix method to calculate frequency band gaps, the second by a generalized function approach. The dynamics of the finite beam is studied in frequency and time domains deriving the exact frequency response and the exact modal response, including modal frequency and impulse response functions. The proposed approach is formulated for arbitrary number of resonators and loads, and applies for both non-proportional and proportional damping