APFELgrid: a high performance tool for parton density determinations

We present a new software package designed to reduce the computational burden of hadron collider measurements in Parton Distribution Function (PDF) fits. The APFELgrid package converts interpolated weight tables provided by APPLgrid files into a more efficient format for PDF fitting by the combination with PDF and $\alpha_s$ evolution factors provided by APFEL. This combination significantly reduces the number of operations required to perform the calculation of hadronic observables in PDF fits and simplifies the structure of the calculation into a readily optimised scalar product. We demonstrate that our technique can lead to a substantial speed improvement when compared to existing methods without any reduction in numerical accuracy.Comment: 13 pages, 2 figures. Submitted to CPC. Code available from https://github.com/nhartland/APFELgri

Sulla pratica clinica affermativa con le persone transgender e gender nonconforming: Nuove linee-guida dell’American Psychological Association

This short essay aims to present the translation and adaptation to the Italian context of the recent guidelines for psychological-clinical practice with transgender and gender nonconforming people (TGNC) published in 2015 by the American Psychological Association (APA). As a result of the confirmation of the psychiatric diagnosis in the latest version of the Diagnostic and Statistical Manual of Mental Disorders (DSM), APA has highlighted the need to use an affirmative practice, that is a respectful, informed, and supportive approach to TGNC identities and life experiences. These guidelines, therefore, represent a fundamental text for a competent and scientifically based psychological cure

Frequency conversion of structured light

We demonstrate the coherent frequency conversion of structured light, optical beams in which the phase varies in each point of the transverse plane, from the near infrared (803nm) to the visible (527nm). The frequency conversion process makes use of sum-frequency generation in a periodically poled lithium niobate (ppLN) crystal with the help of a 1540-nm Gaussian pump beam. We perform far-field intensity measurements of the frequency-converted field, and verify the sought-after transformation of the characteristic intensity and phase profiles for various input modes. The coherence of the frequency-conversion process is confirmed using a mode-projection technique with a phase mask and a single-mode fiber. The presented results could be of great relevance to novel applications in high-resolution microscopy and quantum information processing

Longer aftershocks duration in extensional tectonic settings

Aftershocks number decay through time, depending on several parameters peculiar to each seismogenic regions, including mainshock magnitude, crustal rheology, and stress changes along the fault. However, the exact role of these parameters in controlling the duration of the aftershock sequence is still unknown. Here, using two methodologies, we show that the tectonic setting primarily controls the duration of aftershocks. On average and for a given mainshock magnitude (1) aftershock sequences are longer and (2) the number of earthquakes is greater in extensional tectonic settings than in contractional ones. We interpret this difference as related to the different type of energy dissipated during earthquakes. In detail, (1) a joint effect of gravitational forces and pure elastic stress release governs extensional earthquakes, whereas (2) pure elastic stress release controls contractional earthquakes. Accordingly, normal faults operate in favour of gravity, preserving inertia for a longer period and seismicity lasts until gravitational equilibrium is reached. Vice versa, thrusts act against gravity, exhaust their inertia faster and the elastic energy dissipation is buffered by the gravitational force. Hence, for seismic sequences of comparable magnitude and rheological parameters, aftershocks last longer in extensional settings because gravity favours the collapse of the hangingwall volumes

Collisional quantum thermometry

We introduce a general framework for thermometry based on collisional models, where ancillas probe the temperature of the environment through an intermediary system. This allows for the generation of correlated ancillas even if they are initially independent. Using tools from parameter estimation theory, we show through a minimal qubit model that individual ancillas can already outperform the thermal Cramer-Rao bound. In addition, due to the steady-state nature of our model, when measured collectively the ancillas always exhibit superlinear scalings of the Fisher information. This means that even collective measurements on pairs of ancillas will already lead to an advantage. As we find in our qubit model, such a feature may be particularly valuable for weak system-ancilla interactions. Our approach sets forth the notion of metrology in a sequential interactions setting, and may inspire further advances in quantum thermometry

Noticias desde España vistas desde Italia

Los viajes de ida y vuelta que se han sucedido a lo largo de la historia entre la arquitectura italiana y española han dado lugar a una prolífica correspondencia, materializada en un destacado catálogo de obras y textos. Una mirada desde Italia a la segunda mitad del siglo XX de esta consolidada relación permite destacar una serie de protagonistas cuyas aportaciones han ido determinando, década a década, capítulos claves que nos ayudan a comprender el momento de intenso diálogo que hoy en día podemos apreciar en la arquitectura contemporánea de ambos países