Depinning and dynamics of AC driven vortex lattices in random media

We study the different dynamical regimes of a vortex lattice driven by AC forces in the presence of random pinning via numerical simulations. The behaviour of the different observables is charaterized as a function of the applied force amplitude for different frequencies. We discuss the inconveniences of using the mean velocity to identify the depinnig transition and we show that instead, the mean quadratic displacement of the lattice is the relevant magnitude to characterize different AC regimes. We discuss how the results depend on the initial configuration and we identify new hysteretic effects which are absent in the DC driven systems.Comment: 6 pages, 4 figure

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Relation between width of zero-bias anomaly and Kondo temperature in transport measurements through correlated quantum dots: Effect of asymmetric coupling to the leads

The zero-bias anomaly at low temperatures, originated by the Kondo effect when an electric current flows through a system formed by a spin-1/2 quantum dot and two metallic contacts is theoretically investigated. In particular, we compare the width of this anomaly 2TNE with that of the Kondo resonance in the spectral density of states 2TKρ, obtained from a Fano fit of the corresponding curves and also with the Kondo temperature TKG defined from the temperature evolution of the equilibrium conductance G(T). In contrast to TKG and 2TKρ, we found that the scale 2TNE strongly depends on the asymmetry between the couplings of the quantum dot to the leads while the total hybridization is kept constant. While the three scales are of the same order of magnitude, 2TNE and TKρ agree only in the case of large asymmetry between the different tunneling couplings of the contacts and the quantum dot. On the other hand, for similar couplings, TNE becomes larger than TKρ, reaching the maximum deviation, of the order of 30%, for identical couplings. The fact that an additional parameter to TNE is needed to characterize the Kondo effect, weakening the universality properties, points that some caution should be taken in the usual identification in experiments of the low temperature width of the zero-bias anomaly with the Kondo scale. Furthermore, our results indicate that the ratios TNE/TKG and TKρ/TKG depend on the range used for the fitting.Fil: Perez Daroca, Diego Raul. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Roura Bas, Pablo Gines. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aligia, Armando Ángel. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentin

A new Eliomys from the Upper Miocene of Spain and its implications for the phylogeny of genus

In this paper, we describe a previously unknown species of the glirid Eliomys from the Late Miocene and Early Pliocene Cabriel, Alcoy and Granada basins of southeastern Spain. Eliomys yevesi sp. nov. is characterized by its relative small size, narrow lingual wall and common presence of two centrolophs in the upper molars, and well-developed centrolophids in the lower molars. The new species is the probable ancestor of E. intermedius, which in turn represents the ancestor of the extant E. quercinus. According to its morphologic and biometric features, the origin of E. yevesi sp. nov. is likely to be found in some population of E. truci from the Late Miocene. Based on these affinities, we propose the lineage E. truci–E. yevesi sp. nov.–E. intermedius–E. quercinus, in which there is a trend towards the development of centrolophs, as well as the reduction of accessory crests

It was nice with the brick so now I'll click: The effects of offline and online experience, perceived benefits, and trust on Dutch consumers' online repeat purchase intention

The present study investigated the factors influencing Dutch consumers’ intention to continue purchasing from a brick-and-click clothes shop’s online channel after an initial commercial exchange. Results on the online survey with 513 respondents reveal that their repeat online purchase intention is influenced by the quality of their previous online purchase experience with the retailer, their perception of the benefits associated with online purchasing, and their trust in the retailer. Analysis also shows that respondents’ previous offline purchase experience and online purchase experience contribute to their trust in the retailer. Additionally, respondents’ previous online purchase experience positively influences their perception of the benefits associated with purchasing online. The modified model also shows that respondents’ trust in the retailer positively influences their perceptions of online shopping benefits

Una nota mitológica al texto de Máximo de Tiro

The autor proposes a solution to the difficulties found by some scholars in Maximus Tyrius, VIII 6, p. 65, 114-66, 117 Trapp, where Eris is mentioned among some other homeric deities. An emendation of Eris in Iris is deemed plausible on the basis of paleographical, intertextual, and philolosophical reasons.El autor propone solventar las dificultades que algunos estudiosos han señalado en Máximo de Tiro, VIII 6, p. 65, 114-66, 117 Trapp, debido a la mención de la diosa Eris entre otras divinidades homéricas. Se considera plausible la corrección de Eris en Iris a partir de argumentos de orden paleográfico, intertextual y filosófico

Not That Button but the Other: Misunderstanding and Non-understanding in Helpdesk Encounters Involving Nonnative English Speakers

Purpose: The internationalization of “technical help over the phone“ is tied to the increasing usage of a lingua franca facilitating the interaction between a call center agent and a caller who are both linguistically different. Researchers have noted that interactions between two parties who are nonnative users of the language employed for the encounter are peppered with understanding problems. This study looks into the causes of understanding problems in helpdesk encounters between nonnative speakers of English and the techniques those interacting parties used to resolve or prevent flaws in the conversation. Method: Conversation analysis was used to analyze 25 recorded phone calls, amounting to 750 minutes of data, made in a commercial call center and in the helpdesk of an international academic institute in Enschede, the Netherlands. Results: Analysis of the phone calls reveals that causes of understanding problems between an agent and a caller who are nonnative users of English go beyond asymmetries in their proficiency with the language. Factors such as incomplete information or erroneous inference from the utterance of the partner in the interaction are important triggers for the occurrence of understanding problems. Consequently, call center agents and callers use varied repair and preventative techniques to ensure that understanding problems will not impede the attainment of the primary goal of the encounter -to resolve the product-related problem of the caller. Conclusion: While understanding problems are inevitable in helpdesk encounters, especially those that involved nonnative users of the language employed for the interaction, such problems are hardly attributable to the linguistic differences characterizing interacting parties. It is apparent that helpdesk agents and callers are equipped with varied techniques to resolve understanding problems or to prevent their inceptio