Stefano Ghidinelli, L’interazione poetica. Modi di socializzazione e forme della testualità della poesia italiana contemporanea

Recensiamo Ghidinelli, Stefano. L’interazione poetica. Modi e forme della testualità della poesia italiana contemporanea. Napoli: Guida Editori, 2013. Stampa

Analiticity of the Lyapunov exponent of perturbed toral automorphisms

We consider a dynamical system generated by a perturbation $A_\varepsilon$ of an analytic Anosov diffeomorphism $A_0$ of $\mathbb{T}^d$. We show that, if $A_0$ admit a decomposition of $\mathrm T\mathbb T^d$ in $k$ invariant subspaces, such a decomposition can be extended in an analytic way to $A_\varepsilon$. This implies that the Lyapunov exponents, if non degenerate, are analytic functions of the perturbation

On the effects of strong ionization in medium-order harmonic generation

Strong ionization of the gas medium has significant effects in the process of medium-order harmonic generation. The combined effect of neutral atom depletion and defocusing of the pump beam due to the intensity-dependent density of free electrons, significantly modifies the conversion characteristics and efficiency. For moderate harmonic orders, the yield is optimized for well-defined values of the pump laser intensity that do not depend on the order or on the focusing geometry, but only on the ionization potential of the gas. In particular focusing conditions, the ionization-induced defocusing can effectively guide the pump beam along channels of optimum intensity, thus enhancing the overall conversion efficiency. We demonstrate that a very simple model is able to reproduce all our experimental results in a surprisingly good way

Untangling sustainability reporting: theoretical approaches informing non-financial disclosure

This study analyses different theoretical frameworks used in the literature to explain corporate social and environmental sustainability (SES) reporting. A systematic literature review of 232 scientific articles published in top-tier journals was performed through bibliometric visualizations, quantitative statistics and narrative analyses. Results highlight that legitimacy, institutional, and stakeholder theories most commonly inform studies on SES reporting. Recent works also show the use of theoretical approaches less frequently employed in accounting and management that usually distinguish other research fields, such as sociology, psychology, and communication, highlighting crossfertilization among different research areas. This systematic literature review specifically focuses on the many theories related to SES reporting and offers an extensive overview of theoretical frameworks underpinning thirty years of studies on non-financial disclosure. Moreover, encourages scholars to engage with critical and emerging theories in the study of SES reporting following multidimensional and multidisciplinary perspectives

Adult-type rhabdomyoma of the larynx: clinicopathologic study of an uncommon tumor in a rare location

Rhabdomyoma is an uncommon benign mesenchymal tumor with skeletal muscle differentiation that may occur either in the heart or in extra-cardiac sites. Even though the head and neck region is the most common area of extra-cardiac rhabdomyoma, the larynx is rarely involved. We present the case of an 85-year-old woman who reported a 10-day history of breathing difficulties, dysphagia and dysphonia. A computed tomography scan of the head and neck showed a contrast-enhanced, solid hypopharyngeal-laryngeal neoplasm with well-defined margins causing subtotal obliteration of the right pyriform sinus and a reduction in air lumen of the laryngeal vestibule. The patient underwent complete endoscopic removal of the lesion; histologic examination revealed an adult- type rhabdomyoma based on the histologic features and the immunoreactivity of the neoplastic cells for desmin, myoglobin and muscle-specific actin but not for cytokeratin, S-100, CD68R, chromogranin-A and synaptophysin. Since clinical and imaging features are not specific for rhabdomyoma, histologic examination and immunohistochemical analyses play a central role in the differential diagnosis of the adult-type rhabdomyoma from other laryngeal neoplasms. A correct diagnosis is mandatory to avoid inappropriate treatment

High resolution spectroscopy in the XUV with pairs of mutually coherent and time-delayed laser harmonics

We present a Ramsey technique using high-order harmonics for high-resolution atomic spectroscopy in the extreme ultraviolet. Pairs of time-delayed and phase-coherent harmonic pulses generated by the interaction of ultrashort and intense laser pulses with a noble gas are used to study excited states of krypton