Towards AC-induced optimum control of dynamical localization

It is shown that optimum control of dynamical localization (quantum suppression of classical diffusion) in the context of ultracold atoms in periodically shaken optical lattices subjected to time-periodic forces having equidistant zeros depends on the \textit{impulse} transmitted by the external force over half-period rather than on the force amplitude. This result provides a useful principle for optimally controlling dynamical localization in general periodic systems, which is capable of experimental realization.Comment: 7 pages, 6 figure

Reaction rate calculation with time-dependent invariant manifolds

The identification of trajectories that contribute to the reaction rate is the crucial dynamical ingredient in any classical chemical reactivity calculation. This problem often requires a full scale numerical simulation of the dynamics, in particular if the reactive system is exposed to the influence of a heat bath. As an efficient alternative, we propose here to compute invariant surfaces in the phase space of the reactive system that separate reactive from nonreactive trajectories. The location of these invariant manifolds depends both on time and on the realization of the driving force exerted by the bath. These manifolds allow the identification of reactive trajectories simply from their initial conditions, without the need of any further simulation. In this paper, we show how these invariant manifolds can be calculated, and used in a formally exact reaction rate calculation based on perturbation theory for any multidimensional potential coupled to a noisy environment

Beneficiaries in Modern Greek and Spanish: Description and reassessment of a semantic role

This paper studies the different flavours of beneficiaries in Modern Greek beyond the usual suspects. The purpose of this paper is to give a full account of this function in Modern Greek and to reassess the category benefactive in general. Greek data are compared with those taken from Spanish

Using basis sets of scar functions

We present a method to efficiently compute the eigenfunctions of classically chaotic systems. The key point is the definition of a modified Gram-Schmidt procedure which selects the most suitable elements from a basis set of scar functions localized along the shortest periodic orbits of the system. In this way, one benefits from the semiclassical dynamical properties of such functions. The performance of the method is assessed by presenting an application to a quartic two-dimensional oscillator whose classical dynamics are highly chaotic. We have been able to compute the eigenfunctions of the system using a small basis set. An estimate of the basis size is obtained from the mean participation ratio. A thorough analysis of the results using different indicators, such as eigenstate reconstruction in the local representation, scar intensities, participation ratios, and error bounds, is also presentedThis work was supported by MINECO (Spain), under projects MTM2009-14621 and ICMAT Severo Ochoa SEV-2011-0087, and by CEAL Banco de Santander–UAM. F.R. is grateful for the support from a doctoral fellowship from UPM and the hospitality of the members of the Departamento de Física in the Laboratorio TANDAR–Comisión Nacional de la Energía Atómica, where part of this work was don

Unraveling the highly nonlinear dynamics of KCN molecular system using Lagrangian descriptors

In this work, we identify the phase-space structures which are responsible for the chaotic dynamics observed in KCN molecular system using the Lagrangian descriptors. We show that the vibrational dynamics of this molecule is strongly determined by the invariant manifolds associated with a particular stretching periodic orbit previously described (Párraga et al., 2018). Likewise, the representation of these invariant manifolds on a Poincaré surface of section is also studied, concluding that the intricate depiction that is observed has its origin in the complex behavior of the manifolds, which is a consequence of the strong anharmonicities in the potential energy surfaceThis work has been partially supported by the Grants PID2021-122711NB-C21 and CEX2019-000904-S funded by MCIN/AEI/10.13039/501100011033, by the People Programme (Marie Curie Actions) of the European Union’s Horizon 2020 Research and Innovation Program under Grant No. 734557, and by the Comunidad de Madrid, Spain under the Grant APOYO-JOVENES-4L2UB6-53-29443N (GeoCoSiM) financed within the Plurianual Agreement with the Universidad Politécnica de Madrid, Spain in the line to improve the research of young doctor

Reflections on the future business model of European banks and the supervisory approach

Importantes factores están reconfigurando el sector bancario y redefiniendo los modelos de negocio de las entidades. Las entidades han venido afrontando dificultades estructurales, como un entorno de bajos tipos de interés prolongado o el exceso de capacidad instalada. A esto se añaden otros retos más recientes, como la transformación digital, los nuevos competidores en el mercado bancario y el cambio climático. Adicionalmente, un entorno regulatorio exigente y el impacto del COVID-19 suponen una presión añadida. Como resultado, los bancos europeos no están siendo capaces de producir resultados que cubran el coste del capital, lo que hace necesario afrontar con urgencia estos retos. Para ello, existen distintas estrategias posibles, algunas de ellas complementarias, entre las que se pueden destacar: la reducción de la capacidad instalada, la consolidación bancaria, la diversificación o especialización y la explotación del valor de la banca relacional, así como el aprovechamiento de las oportunidades derivadas de la digitalización y las finanzas sostenibles. El supervisor deberá estar al nivel de los cambios que se produzcan en el entorno bancario y seguir de cerca los procesos de adaptación. El propósito de este artículo es servir de base para el debate, dada la controversia existente y la incertidumbre que rodea a algunas de estas cuestiones en un entorno como el actual, que cambia con rapidez

Reflections on the future business model of European banks and the supervisory approach

Relevant forces are reshaping the banking sector and redefining banks’ business models. On the one hand, banks have been facing structural difficulties, such as a prolonged low interest rate environment and the costs of excess capacity. In addition, banks need to deal with more recently developing challenges, like the digital transformation, the entrance of new competitors in the banking sector and the climate change. A demanding regulatory environment and the impact of the COVID-19 pandemic further aggravate the situation. As a result, European banks are not being able to produce enough returns to cover their cost of capital, making it necessary to urgently face these challenges. To that purpose, banks may adopt different strategies, some of them complementary, among which the following can be highlighted: the reduction of overcapacity, consolidation, diversification or specialisation and the exploitation of the value of long-term relations with clients, as well as taking advantage of the opportunities stemming from digitalization and sustainable finance. Supervisors will need to stay abreast of the changes in the banking environment and closely monitor the adaptation processes. This article is intended to serve as a basis for discussion, given that several of the issues raised are controversial and uncertain under the current fast changing environment

Surgery technique for ovine ruminal cannulation

The study of the ruminants' digestive system is of great interest to improve their productive efficiency. From 1928, in which Schalk and Amadon described the technique of cannulation in one stage for bovine and ovine, are developed numerous modifications of that technique as well as new others. A common problem is that can appear complications as movements of the cannula, increases in size of the fistula by necrosis of the tissue or ruminal fluid leak. The developed technique provides a simplification to the surgery, minimizes the complications and lengthens functional life of the cannula.El estudio del sistema digestivo de los rumiantes es de gran interés para conseguir mejorar su eficiencia productiva. Desde 1928, año en el que Schalk y Amadon describieron la técnica de canulación en una fase para su utilización en bovino y ovino, se desarrollan numerosas modificaciones de esta técnica así como otras nuevas. Un problema común es que pueden aparecer complicaciones como movimientos de la cánula, aumentos de tamaño de la fístula por necrosis o fugas de líquido ruminal. La técnica desarrollada aporta una simplificación a la cirugía, minimiza las complicaciones y alarga vida funcional de la cánula

Enkapsulacija askorbinske kiseline u hidrofobnom silikagelu

Self-assembled hybrid organo-silica sol-gel materials are rapidly expanding for newand novel applications. The microporous solid silica matrix was used as a carrier for the controlled release of ascorbic acid (AA), selected as cargo molecule. One-step synthesis procedure was optimized for the preparation of silica–molecule composites by using tetraethoxysilane and methyltrimethoxysilane as precursors. The hydrophobic silica xerogel matrices were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction. Specific surface area and porosity parameters were determined by Brunauer-Emmett-Teller (BET) technique and the matrix surface morphology by scanning electron microscopy (SEM). The observed release pattern could be interesting for the development of AA-fortified food and for use in food packaging.Hibridni, organsko-silikatni sol-gel materijal sve se više primjenjuje u prehrambenoj industriji. Stoga je kao nosač za kontrolirano otpuštanje askorbinske kiseline upotrijebljen mikroporozni čvrsti silikatni matriks. Optimirana je jednostupanjska sinteza kojom su dobiveni silikatni kompoziti uz pomoć prekurzora: tetraetoksisilana i metiltrimetoksisilana. Matriksi su hidrofobnog silikagela okarakterizirani Fourier transformiranom infracrvenom spektroskopijom (FTIR) i difrakcijom X-zraka. Specifična površina i poroznost matriksa ispitane su Brunaer-Emmett-Teller (BET) metodom, dok su morfološka svojstva površine matriksa određena skenirajućim elektronskim mikroskopom (SEM). Utvrđeno je da se askorbinska kiselina ovako može upotrijebiti za proizvodnju hrane s dodanom vrijednošću, te za pakiranje prehrambenih proizvoda