Magnetic superlattice and finite-energy Dirac points in graphene

We study the band structure of graphene's Dirac-Weyl quasi-particles in a one-dimensional magnetic superlattice formed by a periodic sequence of alternating magnetic barriers. The spectrum and the nature of the states strongly depend on the conserved longitudinal momentum and on the barrier width. At the center of the superlattice Brillouin zone we find new Dirac points at finite energies where the dispersion is highly anisotropic, in contrast to the dispersion close to the neutrality point which remains isotropic. This finding suggests the possibility of collimating Dirac-Weyl quasi-particles by tuning the doping

Multiple magnetic barriers in graphene

We study the behavior of charge carriers in graphene in inhomogeneous perpendicular magnetic fields. We consider two types of one-dimensional magnetic profiles, uniform in one direction: a sequence of N magnetic barriers, and a sequence of alternating magnetic barriers and wells. In both cases, we compute the transmission coefficient of the magnetic structure by means of the transfer matrix formalism, and the associated conductance. In the first case the structure becomes increasingly transparent upon increasing N at fixed total magnetic flux. In the second case we find strong wave-vector filtering and resonant effects. We also calculate the band structure of a periodic magnetic superlattice, and find a wave-vector-dependent gap around zero-energy.Comment: 9 pages, 18 figure

MicroRNAs: New Players in Multiple Myeloma

MicroRNAs (miRNAs) are short non-coding RNAs that play critical roles in numerous cellular processes through post-transcriptional regulating functions. The aberrant role of miRNAs has been reported in a number of hematopoietic malignancies including multiple myeloma (MM). In this review we summarize the current knowledge on roles of miRNAs in the pathogenesis of MM

Geometrical bounds on irreversibility in open quantum systems

Clausius inequality has deep implications for reversibility and the arrow of time. Quantum theory is able to extend this result for closed systems by inspecting the trajectory of the density matrix on its manifold. Here we show that this approach can provide an upper and lower bound to the irreversible entropy production for open quantum systems as well. These provide insights on the thermodynamics of the information erasure. Limits of the applicability of our bounds are discussed, and demonstrated in a quantum photonic simulator

Bridging thermodynamics and metrology in non-equilibrium Quantum Thermometry

Single-qubit thermometry presents the simplest tool to measure the temperature of thermal baths with reduced invasivity. At thermal equilibrium, the temperature uncertainty is linked to the heat capacity of the qubit, however the best precision is achieved outside equilibrium condition. Here, we discuss a way to generalize this relation in a non-equilibrium regime, taking into account purely quantum effects such as coherence. We support our findings with an experimental photonic simulation.Comment: 7 pages, 4 figure

Toward validation of simulated accelerograms via prediction equations for nonlinear SDOF response

Seismic structural risk analysis of critical facilities may require nonlinear dynamic analysis for which record selection is one of the key issues. Notwithstanding the increasing availability of database of strong-motion records, it may be hard to find accelerograms that fit a specific scenario (e.g., in terms of magnitude and distance) resulting from hazard assessment at the site of interest. A possible, alternative, approach can be the use of artificial and/or simulated ground motion in lieu of real records. Their employment requires systematic engineering validation in terms of structural response and/or seismic risk. Prediction equations for peak and cyclic inelastic single degree of freedom systems’ response, based on Italian accelerometric data, are discussed in this study as a possible benchmark, alongside real record counterparts, for the validation of synthetic records. Even if multiple events would be in principle required, an extremely preliminary validation is carried out considering only four simulated records of the 1980 Irpinia (southern Italy) M w 6.9 earthquake. Simulated records are obtained through a broadband hybrid integral-composite technique. Results show how this simulation method may lead to generally acceptable results. It is also emphasized how this kind of validation may provide additional results with respect to classical signal-to-signal comparison of real and simulated records

Analysing Bicycle Parking in Barcelona : Geospatial Insights

Aquest article estudia els aparcaments de bicicletes des d'una perspectiva geoespacial. Les bicicletes ofereixen nombrosos avantatges respecte als cotxes, sent més saludables, ecològiques i assequibles, especialment en entorns urbans. No obstant això, un aparcament inadequat pot provocar danys i robatoris, obstaculitzant l'adopció de la bicicleta com a mitjà de transport. La literatura existent sol tractar les bicicletes com a entitats dinàmiques i ignora el seu caràcter estàtic durant l'aparcament. Els objectius principals inclouen analitzar la distribució dels aparcaments a la ciutat, quantificar el temps necessari per accedir-hi i tornar-ne, i investigar correlacions entre l'ocupació i la proximitat a la infraestructura municipal. Els resultats aporten informació valuosa per optimitzar l'aparcament de bicicletes, fomentant així una transició cap a una mobilitat urbana més sostenible.Este artículo examina, desde una perspectiva geoespacial, las infraestructuras de aparcamiento para bicicletas y sus implicaciones para la movilidad urbana. Las bicicletas ofrecen numerosas ventajas frente a los coches: son más sanas, más ecológicas y más asequibles, sobre todo en entornos urbanos. Sin embargo, un aparcamiento inadecuado de bicicletas puede provocar daños y robos, lo que dificulta su adopción. La literatura existente trata principalmente las bicicletas como entidades dinámicas, ignorando su naturaleza estática durante el estacionamiento. Este estudio aborda esta carencia investigando la distribución, proximidad y datos de ocupación de los aparcamientos de bicicletas en una ciudad. Los objetivos son analizar la distribución de los aparcamientos en la ciudad, cuantificar el tiempo que se tarda en acceder a ellos y en volver, e investigar las correlaciones entre ocupación y proximidad a las infraestructuras municipales. Los resultados de la investigación aportan información valiosa para optimizar el aparcamiento de bicicletas, fomentando así una transición hacia una movilidad urbana más sostenible.This paper examines the often overlooked topic of bicycle parking infrastructure and it's implications for urban mobility from a geospatial perspective. Bicycles offer numerous benefits over cars, being healthier, greener, and more affordable, particularly in urban environments. However, inadequate bicycle parking can lead to damage and theft, hindering cycling adoption. Existing literature mainly treats bicycles as dynamic entities while ignoring their static nature during parking. This study addresses this gap by investigating bicycle parking distribution, proximity, and occupancy data in a city. The goals involve analyzing parking facility distribution across the city, quantifying walking time to access and return from facilities, and investigating correlations between occupancy and proximity to municipal infrastructure. The research findings provide valuable insights into optimizing bicycle parking, thus fostering a transition towards more sustainable urban mobility