1,720,988 research outputs found
Neutralita di genere nella valutazione
Full text linkWe report a gender analysis of the results of the national evaluation processes “Evaluation of research quality” (VQR, 2004-2010) and “National Scientific Habilitation” (ASN, 2012-2013), adopted in Italy to assign research funding, and to decide career progressions respectively. In both cases the chosen criteria are observed to be non neutral, in favor of the male gender. In case of VQR the differences are on average of the order of 3%, while higher in some areas. They also capture the presence of vertical segregation, through the significantly higher female score in each role and area at the end of career. In case of ASN, where different criteria were chosen, their non neutrality is estimated to be of the order of 10%, and much higher in terms of potential habilitations per gender. It is suggested that gender neutrality of criteria should be mandatorily verified
Evoluzione della tecnica nel colloquio psicodinamico. Un percorso storico
No full textQuesto testo considera, da un punto di vista storico, l’evoluzione della teoria della tecnica in ambito psicoanalitico. In questo percorso è possibile notare come idee brillanti ed innovative, lette talvolta come provocatori cambiamenti di paradigma nella concezione della relazione terapeutica, abbiano avuto bisogno di tempo, anche svariati decenni, per essere accolte e valorizzate dalla comunità scientifica. Si assiste così alla “riscoperta”, da parte di un autore successivo, di prospettive cliniche che già autori precedenti avevano individuato e teorizzato. Impossibile a questo proposito non citare Sándor Ferenczi, il cui pensiero appare, sotto diverse vesti, nelle elaborazioni di molti autori che gli sono succeduti (non solo quelli considerati in questo testo).
Le spinte che hanno portato a proporre delle modificazioni nella tecnica sono nate sia dal volerla rendere più efficace, sia dal volerla adattare ad un’utenza il più ampia possibile. In questo senso, ripercorrere i pensieri, i dubbi e le esigenze di ciascun autore può, almeno in parte, rappresentare il percorso che un clinico implicitamente mette in atto nella riflessione quotidiana che segue l’attività terapeutica.
Passando da Freud a Ferenczi, da Alexander a Kohut per arrivare a Weiss, diverse sono le prospettive che arricchiscono l’approccio clinico: dall’attenzione alla relazione, alla struttura soggettiva, alla qualità delle esperienze emotive che favoriscono il cambiamento, alle risorse ed ai piani inconsci del paziente. Sempre di più assistiamo a come l’attenzione passi da una “meccanica” applicazione di un precetto tecnico ad una visione della tecnica come inscindibile dalle esigenze, dalla storia e dalla struttura del paziente. Questo insieme di attenzioni viene, a nostro avviso, ben riassunto da Orange, Atwood e Stolorow, quando affermano: “Considerare il lavoro clinico come una tecnica è un fatto ancora pervasivo e gravemente dannoso”
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Quantum discord and classical correlations in the bond-charge Hubbard model: Quantum phase transitions, off-diagonal long-range order, and violation of the monogamy property for discord
No full textWe study the quantum discord (QD) and the classical correlations (CC) in a reference model for strongly correlated electrons, the one-dimensional bond-charge extended Hubbard model. We show that the comparison of QD and CC and of their derivatives in the direct and reciprocal lattice allows one to efficiently inspect the structure of two-points driven quantum phase transitions, discriminating those at which off diagonal long-range order (ODLRO) is involved. Moreover, we observe that QD between pair of sites is a monotonic function of ODLRO, thus establishing a direct relation between the latter and two point quantum correlations that differ from the entanglement. The study of the ground-state properties allows us to show that for a whole class of permutation invariant (η-pair) states quantum discord can violate the monogamy property, both in presence and in absence of bipartite entanglement. In the thermodynamic limit, due to the presence of ODLRO, the violation for η-pair states is maximal, while, for the purely fermionic ground state, it is finite. From a general perspective, all our results validate the importance of the concepts of QD and CC for the study of critical condensed-matter systems. © 2011 American Physical Society
Hubbard model on triangular N -leg cylinders: Chiral and nonchiral spin liquids
Full text linkThe existence of a gapped chiral spin liquid has been recently suggested in the vicinity of the metal-insulator transition of the Hubbard model on the triangular lattice, by intensive density-matrix renormalization group (DMRG) simulations [A. Szasz, J. Motruk, M. P. Zaletel, and J. E. Moore, Phys. Rev. X 10, 021042 (2020)10.1103/PhysRevX.10.021042]. Here, we report the results obtained within the variational Monte Carlo technique based upon Jastrow-Slater wave functions, implemented with backflow correlations. As in DMRG calculations, we consider N-leg cylinders. For N=4 and in the presence of a next-nearest-neighbor hopping, a chiral spin liquid emerges between the metal and the insulator with magnetic quasi-long-range order. Within our approach, the chiral state is gapped and breaks the reflection symmetry. By contrast, for both N=5 and 6, the chiral spin liquid is not the state with the lowest variational energy: in the former case, a nematic spin liquid is found in the entire insulating regime, while for the less frustrated case with N=6 the results are very similar to that obtained on two-dimensional clusters [L. F. Tocchio, A. Montorsi, and F. Becca, Phys. Rev. B 102, 115150 (2020)2469-995010.1103/PhysRevB.102.115150], with an antiferromagnetic phase close to the metal-insulator transition and a nematic spin liquid in the strong-coupling regime
Magnetic and spin-liquid phases in the frustrated t-t′ Hubbard model on the triangular lattice
Full text linkThe Hubbard model and its strong-coupling version, the Heisenberg one, have been widely studied on the triangular lattice to capture the essential low-temperature properties of different materials. One example is given by transition metal dichalcogenides, as 1T-TaS2, where a large unit cell with 13 Ta atoms forms weakly coupled layers with an isotropic triangular lattice. By using accurate variational Monte Carlo calculations, we report the phase diagram of the t-t′ Hubbard model on the triangular lattice, highlighting the differences between positive and negative values of t′/t; this result can be captured only by including the charge fluctuations that are always present for a finite electron-electron repulsion. Two spin-liquid regions are detected: one for t′/t0. The spin-liquid phase appears to be gapless, though the variational wave function has a nematic character, in contrast to the Heisenberg limit. We do not find any evidence for nonmagnetic Mott phases in the proximity of the metal-insulator transition, at variance with the predictions (mainly based upon strong-coupling expansions in t/U) that suggest the existence of a weak-Mott phase that intrudes between the metal and the magnetically ordered insulator
Hubbard model on triangular N-leg cylinders: Chiral and nonchiral spin liquids
Full text linkThe existence of a gapped chiral spin liquid has been recently suggested in the vicinity of the metal-insulator transition of the Hubbard model on the triangular lattice, by intensive density-matrix renormalization group (DMRG) simulations [A. Szasz, J. Motruk, M. P. Zaletel, and J. E. Moore, Phys. Rev. X 021042 (2020)]. Here, we report the results obtained within the variational Monte Carlo technique based upon Jastrow-Slater wave functions, implemented with backflow correlations. As in DMRG calculations, we consider N-leg cylinders. For N = 4 and in the presence of a next-nearest-neighbor hopping, a chiral spin liquid emerges between the metal and the insulator with magnetic quasi-long-range order. Within our approach, the chiral state is gapped and breaks the reflection symmetry. By contrast, for both N = 5 and 6, the chiral spin liquid is not the state with the lowest variational energy: in the former case, a nematic spin liquid is found in the entire insulating regime, while for the less frustrated case with N = 6 the results are very similar to that obtained on two-dimensional clusters [L. F. Tocchio, A. Montorsi, and F. Becca, Phys. Rev. B 102, 115150 (2020)], with an antiferromagnetic phase close to the metal-insulator transition and a nematic spin liquid in the strong-coupling regime
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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