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Abstract In this paper we investigate the vacuum stability of the non-minimally coupled Standard-Model Higgs during a phase of kinetic domination following the end of inflation. The non-minimal coupling to curvature stabilises the Higgs fluctuations during inflation while driving them towards the instability scale during kination, when they can classically overcome the potential barrier separating the false electroweak vacuum from the true one at super-Planckian field values. Avoiding the instability of the Standard-Model vacuum sets an upper bound on the inflationary scale that depends both on the strength of the non-minimal interaction and on the top quark Yukawa coupling. Classical vacuum stability is guaranteed if the gravitationally-produced energy density is smaller than the height of barrier in the effective potential. Interestingly enough, thanks to the explosive particle production in the tachyonic phase, the Higgs itself can be also appointed to the role of reheaton field responsible for the onset of the hot Big Bang era, setting an additional lower bound on the inflationary scale H inf $$ {\mathcal{H}}_{\textrm{inf}} $$ ≳ 105.5 GeV. Overall, these constraints favour lower masses for the top quark, in agreement with the current measurements of the top quark pole mass. We perform our analysis semi-analytically in terms of the one-loop and three-loop running of the Standard-Model Higgs self-coupling and make use of lattice-based parametric formulas for studying the (re)heating phase derived in arXiv:2307.03774. For a specific choice of m t = 171.3 GeV we perform also an extensive numerical scanning of the parameter space via classical lattice simulations, identifying stable/unstable regions and supporting the previous analytical arguments. For this fiducial value, the heating of the Universe is achieved at temperatures in the range 10−2–109 GeV.

The Eisenhart lift allows formulating the dynamics of a scalar field in a potential as pure geodesic motion in a curved field-space manifold involving an additional fictitious vector field. Making use of the formalism in the context of inflation, we show that the main inflationary observables can be expressed in terms of the geometrical properties of a two-dimensional uplifted field-space manifold spanned by the time derivatives of the scalar and the temporal component of the vector. This allows to abstract from specific potentials and models and describe inflation solely in terms of the flow of geometric quantities. Our findings are illustrated through several inflationary examples previously considered in the literature.

Abstract The detection of a stochastic Gravitational Wave (GW) background sourced by a cosmological phase transition would allow us to see the early Universe from a completely new perspective, illuminating aspects of Beyond the Standard Model (BSM) physics and inflationary cosmology. In this study, we investigate whether the evolution of the scalar potential of a minimal SM extension after inflation can lead to a strong first-order phase transition. In particular, we focus on a BSM spectator scalar field that is non-minimally coupled to gravity and has a dynamical double-well potential. As inflation ends, the potential barrier diminishes due to the evolution of the curvature scalar. Therefore, a phase transition can proceed through the nucleation of true-vacuum bubbles that collide as they fill the Universe and produce GWs. We consider high and low scales of inflation, while also taking into account a kination period between inflation and the onset of radiation domination. With this prescription, we showcase a proof-of-concept study of a new triggering mechanism for BSM phase transitions in the early Universe, whose GW signatures could potentially be probed with future detectors.

Este artículo analiza la novela de Jorge Enrique Lage (1979), La autopista: The movie, en el contexto de la última narrativa cubana y la ciencia ficción caribeña. Muchas de las obras de Lage exploran las diferentes posibilidades del futuro de Cuba, planteando universos llenos de elementos extraños y novedosos que se pueden corresponder —o no— con el futuro del país, aunque no construye una sociedad modélica: estos universos están sumidos en el caos, en la inestabilidad. La globalización entra en sus novelas como una fuerza irremediable y es la causa de la llegada de todos estos elementos a la isla.

Kazrin is a protein widely expressed in vertebrates whose depletion causes a myriad of developmental defects, in part derived from altered cell adhesion and migration, as well as failure to undergo epidermal to mesenchymal transition. However, the primary molecular role of kazrin, which might contribute to all these functions, has not been elucidated yet. We previously identified one of its isoforms, kazrin C, as a protein that potently inhibits clathrin-mediated endocytosis when overexpressed. We now generated kazrin knock-out mouse embryonic fibroblasts to investigate its endocytic function. We found that kazrin depletion delays juxtanuclear enrichment of internalized material, indicating a role in endocytic traffic from early to recycling endosomes. Consistently, we found that the C-terminal domain of kazrin C, predicted to be an intrinsically disordered region, directly interacts with several early endosome (EE) components, and that kazrin depletion impairs retrograde motility of these organelles. Further, we noticed that the N-terminus of kazrin C shares homology with dynein/dynactin adaptors and that it directly interacts with the dynactin complex and the dynein light intermediate chain 1. Altogether, the data indicate that one of the primary kazrin functions is to facilitate endocytic recycling by promoting dynein/dynactin-dependent transport of EEs or EE-derived transport intermediates to the recycling endosomes.

The effective scaling-up of redox flow batteries (RFBs) can be facilitated upon lowering the capital costs. The application of ubiquitous manganese along with hydrogen (known as H2−Mn regenerative fuel cells (RFC)) is seen as an effective solution for this purpose. Here, we aim to evaluate different positive electrodes so as to improve the key performance metrics of the H2/Mn RFC, namely electrolyte utilization, energy efficiency, and peak power densities. Commercially available carbon paper and graphite felt are used to show that the latter provides better key performance indicators (KPIs), which is consistent with the results reported for standard all-vanadium RFBs in the literature. Even better KPIs are obtained when an in-house carbon catalyst layer (CCL) is employed in combination with graphite felt electrodes (e.g., more than 80% energy efficiency, >0.5 W cm−2 peak power density and electrolyte utilization of 20 Ah L−1 for felt and carbon metal fabric (CMF), prepared by means of electrospinning and carbonization, in comparison with about 75% energy efficiency 0.45 W cm−2 peak power density and 11 Ah L−1 electrolyte utilization for felt on its own). It is envisaged that if the electrochemical performance of CCLs can be optimized then it could open up new opportunities for the commercial exploitation of H2−Mn systems.

Vehicular ad-hoc networks (VANETs) are mobile networks with highly dynamic contexts of operation. The design and application of context-aware systems could be critical to enhance the performance of protocols deployed in VANETs, which depend on both network and traffic conditions, to detect hostile communication environments, as well as to offer a novel way to make decisions in real-time. In this paper, we present a baseline study for the design of a context-aware system for dissemination of safety messages in VANETs. We model a realistic vehicular intersection and perform extensive simulations to evaluate two well-known dissemination mechanisms, namely the Slotted 1-persistence and the Traffic Adaptive Data Dissemination (TrAD) Protocol, with a set of parameters according to different operation scenarios. We show how the dissemination mechanisms’ performance could be improved, or worsened, by choosing a different set of parameter values. By characterizing the operation scenarios, it is possible to adequate the parameters of the dissemination mechanism with the values that work best in a given context, improving in this way the general performance of the dissemination mechanisms under study.

Abstract This paper considers a broadcast multiple-input multiple-output (MIMO) network with multiple users and simultaneous wireless information and power transfer (SWIPT). In this scenario, it is assumed that some users are able to harvest power from radio frequency (RF) signals to recharge batteries through wireless power transfer from the transmitter, while others are served simultaneously with data transmission. The criterion driving the optimization and design of the system is based on the weighted sum rate for the users being served with data. At the same time, constraints stating minimum per-user harvested powers are included in the optimization problem. This paper derives the structure of the optimal transmit covariance matrices in the case where both types of users are present simultaneously in the network, particularizing the results to the cases where either only harvesting nodes or only information users are to be served. The trade-off between the achieved weighted sum rate and the powers harvested by the user terminals is analyzed and evaluated using the rate-power (R-P) region. Finally, we propose a two-stage user grouping mechanism that decides which users should be scheduled to receive information and which users should be configured to harvest energy from the RF signals in each particular scheduling period, this being one of the main contributions of this paper.

It has been argued that oscillatory features from spectator fields in the primordial power spectrum could be a probe of alternatives to inflation. In this work, we soften this claim by showing that the frequency and amplitude dependence of the patterns appearing in these scenarios could be mimicked by field interactions during inflation. The degeneracy of the frequency holds for the n-point correlation functions, while the degeneracy of the amplitude is broken at the level of non-gaussianities. Keywords: Inflation, Early universe, Primordial features, Primordial standard clocks, Alternatives to inflation

The Objective Structured Clinical Exam (OSCE) is an assessment tool used as a reliable method for clinical competence evaluation of students. This paper presents an investigation focused on the chain of survival, its related exploration, management, and technical skills, and how Virtual Reality (VR) can be used for the creation of immersive environments capable of evaluating students’ performance while applying the correct protocols. In particular, the Cardiopulmonary Resuscitation (CPR) procedure is studied as an essential step in the development of the chain of survival. The paper also aims to highlight the limitations of traditional methods using mechanical mannequins and the benefits of the new approaches that involve the students in virtual, immersive, and dynamic environments. Furthermore, an immersive VR station is presented as a new technique for assessing CPR performance through objective data collection and posterior evaluation. A usability test was carried out with 33 clinicians and OSCE evaluators to test the viability of the presented scenario, reproducing conditions of a real examination. Results suggest that the environment is intuitive, quick, and easy to learn and could be used in clinical practice to improve CPR performance and OSCE evaluation.

We point out that the successful generation of the electroweak scale via gravitational instanton configurations in certain scalar-tensor theories can be viewed as the aftermath of a simple requirement: the existence of a quadratic pole with a sufficiently small residue in the Einstein-frame kinetic term for the Higgs field. In some cases, the inflationary dynamics may also be controlled by this residue and therefore related to the Fermi-to-Planck mass ratio, up to possible uncertainties associated with the instanton regularization. We present here a unified framework for this hierarchy generation mechanism, showing that the aforementioned residue can be associated with the curvature of the Einstein-frame target manifold in models displaying spontaneous breaking of dilatations. Our findings are illustrated through examples previously considered in the literature.

Industry 4.0 constitutes a major application domain for sensor data analytics. Industrial furnaces (IFs) are complex machines made with special thermodynamic materials and technologies used in industrial production applications that require special heat treatment cycles. One of the most critical issues while operating IFs is the emission of black carbon (EoBC), which is due to a large number of factors such as the quality and amount of fuel, furnace efficiency, technology used for the process, operation practices, type of loads and other aspects related to the process conditions or mechanical properties of fluids at furnace operation. This paper presents a methodological approach to predict EoBC during the operation of IFs with the use of predictive models of machine learning (ML). We make use of a real data set with historical operation to train ML models, and through evaluation with real data we identify the most suitable approach that best fits the characteristics of the data set and implementation constraints in real production environments. The evaluation results confirm that it is possible to predict the undesirable EoBC well in advance, by means of a predictive model. To the best of our knowledge, this paper is the first approach to detail machine-learning concepts for predicting EoBC in the IF industry.

Quintessential inflation provides a unified description of inflation and dark energy in terms of a single scalar degree of freedom, the cosmon. We present here a comprehensive overview of this appealing paradigm, highlighting its key ingredients and keeping a reasonable and homogeneous level of details. After summarizing the cosmological evolution in a simple canonical case, we discuss how quintessential inflation can be embedded in a more general scalar-tensor formulation and its relation to variable gravity scenarios. Particular emphasis is placed on the role played by symmetries. In particular, we discuss the evolution of the cosmon field in terms of ultraviolet and infrared fixed points potentially appearing in quantum gravity formulations and leading to the emergence of scale invariance in the early and late Universe. The second part of the review is devoted to the exploration of the phenomenological consequences of the paradigm. First, we discuss how direct couplings of the cosmon field to matter may affect neutrinos masses and primordial structure formation. Second, we describe how Ricci-mediated couplings to spectator fields can trigger the spontaneous symmetry breaking of internal symmetries such as, but not limited to, global U(1) or Z2 symmetries, and affect a large variety of physical processes in the early Universe.

We present a novel Affleck–Dine scenario for the generation of the observed baryon asymmetry of the Universe based on the non-trivial interplay between quintessential inflationary models containing a kinetic dominated post-inflationary era and a non-minimally coupled U(1) field with a weakly broken B−L symmetry. The non-minimal coupling to gravity renders heavy the Affleck–Dine field during inflation and avoids the generation of isocurvature fluctuations. During the subsequent kinetic era the Ricci scalar changes sign and the effective mass term of the Affleck–Dine field becomes tachyonic. This allows the field to dynamically acquire a large expectation value. The symmetry of the Affleck–Dine potential is automatically restored at the onset of radiation domination, when the Ricci scalar approximately equals zero. This inverse phase transition results in the coherent oscillation of the scalar field around the origin of its effective potential. The rotation of the displaced Affleck–Dine field in the complex plane generates a non-zero B−L asymmetry which can be eventually converted into a baryon asymmetry via the usual transfer mechanisms.

Abstract This paper provides a methodology for the dimensioning of the access network in remote rural areas, considering the progressive introduction of cellular services in these regions. A 3G small cell (SC) network with one or several carriers deployed at the SC, fed with solar panels and connected to a backhaul with limited capacity is considered for the analysis. Because the backhaul may be inexistent or very expensive (e.g., satellite-based backhaul) the network design pursues the minimization of the required backhaul bandwidth. The required backhaul bandwidth and the required energy units (i.e., the size of the solar panels and the required number of batteries) are then obtained as an output of the dimensioning analysis. Both the backhaul minimization objective and the constraints associated with each of the carriers (low maximum radiated power and low number of users connected simultaneously) require a novel methodology compared to the classical dimensioning techniques. We also develop a procedure for switching on/off carriers in order to minimize the energy consumption without affecting the quality of service (QoS) perceived by the users. This technique allows reducing the required size of the energy units, which directly translates into a cost reduction. In the development of this on/off switching strategy, we first assume perfect knowledge of the traffic profile and later, we develop a robust Bayesian approach to account for possible error modeling in the traffic profile information.

Abstract This paper deals with the development of several strategies for associating users to base stations (BSs) in heterogeneous networks. These strategies are able to balance the rate among users and BSs and increase the overall network utility. Constraints related to the energy availability at BSs are considered explicitly in the design, assuming that the BSs are equipped with batteries that are recharged through energy harvesting. We develop a general association strategy, and then we present several suboptimum but less complex solutions suitable for scenarios with high mobility or deployments of BSs with low computational capabilities. We also present an implementation that is to be executed in a distributed way among users and BSs without the need of having a central entity gathering all the information. The performance of the proposed strategies is evaluated through simulations in terms of rate balancing and the effect of the energy harvesting capabilities on the network throughput is shown. We also compare the proposed strategies with the traditional max-SINR user association approach.

The properties of the recently discovered Higgs boson together with the absence of new physics at collider experiments allows us to speculate about consistently extending the Standard Model of particle physics all the way up to the Planck scale. In this context, the Standard Model Higgs non-minimally coupled to gravity could be responsible for the symmetry properties of the Universe at large scales and for the generation of the primordial spectrum of curvature perturbations seeding structure formation. We overview the minimalistic Higgs inflation scenario, its predictions, open issues and extensions and discuss its interplay with the possible metastability of the Standard Model vacuum.

One of the main preventable leading causes of death after a trauma injury is the hemorrhagic shock. Therefore, it is extremely important to learn how to control hemorrhages. In this paper, a hemorrhagic trauma simulator for lower limb has been developed and a pilot study has been accomplished to trail the simulator. Four different bleeding scenarios have been tested per participant, gathering information about the manual pressure exerted to control the bleeding. Data, altogether, from 54 hemorrhagic scenarios managed by final year medical students and doctors were gathered. Additionally, a post-simulation questionnaire, related to the usability of the simulator, was completed. All the participants managed to control the simulated bleeding scenarios, but the pressure exerted to control the four different scenarios is different depending if the trainee is a student or a doctor, especially in deep venous hemorrhages. This research has highlighted the different approach to bleeding control treatment between medical students and doctors. Moreover, this pilot study demonstrated the need to deliver a more effective trauma treatment teaching for hemorrhagic lesions and that hemorrhagic trauma simulators can be used to train and evaluate different scenarios.

We consider a minimally-coupled inflationary theory with a general scalar potential V(f(φ))=V(ξ∑k=1nλkφk) containing a stationary point of maximal order m. We show that asymptotically flat potentials can be associated to stationary points of infinite order and discuss the relation of our approach to the theory of α-attractors.

We study the geometrical properties of scale-invariant two-field models of inflation. In particular, we show that when the field-derivative space in the Einstein frame is maximally symmetric during inflation, the inflationary predictions can be universal and independent of the details of the theory.

Common issues aqueous-based vanadium redox flow batteries (VRFBs) face include low cell voltage due to water electrolysis side reactions and highly corrosive and environmentally unfriendly electrolytes (3 to 5 M sulfuric acid). Therefore, this investigation looks into the comparison of a highly conductive ionic liquid with a well-studied deep eutectic solvent (DES) as electrolytes for non-aqueous VRFBs. The latter solvent gives 50% higher efficiency and capacity utilization than the former. These figures of merit increase by 10% when nitrogen-doped graphene (N-G)-modified carbon papers, via a one-step binder-free electrophoretic deposition process, are used as electrodes. X-ray computed tomography confirms the enhancement of electrochemical surface area of the carbon electrodes due to N-G while electrochemical impedance spectra show the effect of its higher conductivity on improving RFB performance. Finally, potential strategies for the scaling-up of DES-based VRFBs using a simple economical model are also briefly discussed. From this study, it is deduced that more investigations on applying DESs as non-aqueous electrolytes to replace the commonly used acetonitrile may be a positive step forward because DESs are not only cheaper but also safer to handle, far less toxic, non-flammable, and less volatile than acetonitrile.

Vehicular ad-hoc Networks (VANETs) are recognized as a cornerstone of Intelligent Transportation Systems (ITS) to enable the exchange of information among vehicles, which is crucial for the provision of safety-related and entertainment applications. However, practical useful realizations of VANETs are still missing, mainly because of the elevated costs and the lack of a final standardization. In this regard, the feasibility of using smartphones as nodes in VANETs has been explored focusing on small-scale deployments to mainly validate single-hop communication capabilities. Moreover, existing smartphone-based platforms do not consider two crucial requirements in VANETs, namely, multi-hop communication and the provision of security services in the message dissemination process. Furthermore, the problem of securing message dissemination in VANETs is generally analyzed through simulation tools, while performance evaluations on smart devices have not been reported so far. In this paper, we aim to fill this void by designing a fully on-device platform for secure multi-hop message dissemination. We address the multi-hop nature of message dissemination in VANETs by integrating a location-based protocol that enables the selection of relay nodes and retransmissions criteria. As a main distinction, the platform incorporates a novel certificateless cryptographic scheme for ensuring data integrity and nodes’ authentication, suitable for VANETs lacking of infrastructure.

The disruptive innovation of smartphone technology has enabled the development of mobile sensing applications leveraged on specialized sensors embedded in the device. These novel mobile phone applications rely on advanced sensor information processes, which mainly involve raw data acquisition, feature extraction, data interpretation and transmission. However, the continuous accessing of sensing resources to acquire sensor data in smartphones is still very expensive in terms of energy, particularly due to the periodic use of power-intensive sensors, such as the Global Positioning System (GPS) receiver. The key underlying idea to design energy-efficient schemes is to control the duty cycle of the GPS receiver. However, adapting the sensing rate based on dynamic context changes through a flexible middleware has received little attention in the literature. In this paper, we propose a novel modular middleware architecture and runtime environment to directly interface with application programming interfaces (APIs) and embedded sensors in order to manage the duty cycle process based on energy and context aspects. The proposed solution has been implemented in the Android software stack. It allows continuous location tracking in a timely manner and in a transparent way to the user. It also enables the deployment of sensing policies to appropriately control the sampling rate based on both energy and perceived context. We validate the proposed solution taking into account a reference location-based service (LBS) architecture. A cloud-based storage service along with online mobility analysis tools have been used to store and access sensed data. Experimental measurements demonstrate the feasibility and efficiency of our middleware, in terms of energy and location resolution.

Vehicular ad hoc networks (VANETs) have been identified as a key technology to enable intelligent transport systems (ITS), which are aimed to radically improve the safety, comfort, and greenness of the vehicles in the road. However, in order to fully exploit VANETs potential, several issues must be addressed. Because of the high dynamic of VANETs and the impairments in the wireless channel, one key issue arising when working with VANETs is the multihop dissemination of broadcast packets for safety and infotainment applications. In this paper a reliable low-overhead multihop broadcast (RLMB) protocol is proposed to address the well-known broadcast storm problem. The proposed RLMB takes advantage of the hello messages exchanged between the vehicles and it processes such information to intelligently select a relay set and reduce the redundant broadcast. Additionally, to reduce the hello messages rate dependency, RLMB uses a point-to-zone link evaluation approach. RLMB performance is compared with one of the leading multihop broadcast protocols existing to date. Performance metrics show that our RLMB solution outperforms the leading protocol in terms of important metrics such as packet dissemination ratio, overhead, and delay.

En este artículo se ofrece en breve síntesis la situación de la España de la Restauración (1875-1895) desde el punto de vista internacional, a través de la mas destacadas iniciativas de sus gobernantes y otras significativas páginas del lapso contemplado. Una síntesis que no excluye la revisión de importantes mitos hasta ahora vigentes en nuestra historiografía, y la aportación de nuevos análisis, fruto de amplias investigaciones durante largos años en archivos españoles y extranjeros.

Con ocasión de la conmemoración en España del «Quinto Centenario», se hizo público el deseo de amplios sectores de la comunidad judía, dentro y fuera de España, de que el edicto de expulsión de 1492 fuera derogado de modo simbólico, pero expreso, por el Gobierno español. No era la primera vez que se solicitaba la derogación del edicto, ya que desde mediados del siglo XIX se habían recibido otras peticiones, en dicho sentido, por los Gobiernos españoles. En el presente trabajo se recuerdan todas estas peticiones y se muestra que el edicto de expulsión había sido revocado ya en el siglo pasado. No sólo porque la constitución de 1869, y las posteriores, lo derogaban implícitamente, sino porque el Gobierno español que tomó el poder en 1868 lo derogó expresamente, en noviembre de dicho año, haciéndolo público en un importante acto político y difundiéndose la noticia por toda España. La simbólica derogación expresa que se solicitaba para 1992, había sido ya realizada por el Gobierno español 124 años antes.

El Coloquio con el título indicado, y organizado por los correspondientes Departamentos de Historia de la Universidad de Salamanca y de la UNED, así como por la Sección Guerra Civil del Archivo Histórico Nacional, que se desarrollará en Salamanca los días 2, 3 y 4 de mayo del próximo año 1991, constituye, como es sabido, la manifestación española antecedente al Coloquio Internacional que en noviembre de 1991 tendrá lugar en París sobre Italiens et Espagnols en France 1938-1946. Coloquio este último que se organiza bajo el triple patrocinio del «Centre d'Histoire de l'Europe du Vingtième Siècle, del «Centre de Documentation sur l'Emigration Italienne » y del «Institut d'Histoire du Temps Présent» (IHTP en lo sucesivo). Esta última entidad, el IHTP, ha tenido ya la feliz iniciativa de encomendar a dos distinguidos historiadores franceses la fijación del estado de la cuestión de la temática del Coloquio de París, en cuanto a bibliografía, en cada una de sus vertientes nacionales. Eric Vial, profesor de la Universidad de Provence, ha sido el encargado de la investigación bibliográfica relativa a los italianos, y Geneviève Dreyfus, conservadora- jefe de la Biblioteca Internacional de Documentación Contemporánea de Nanterre, ha tenido a su cargo la parte relativa a los españoles.

RESUMEN: En la historiografía española se ha considerado desde hace largo tiempo que la política exterior de Cánovas era esencialmente de voluntario recogimiento (en francés recueillement). Es decir, una política que suponía el deliberado propósito de apartamiento de alianzas y de importantes compromisos internacionales. En el presente artículo se muestra que la política internacional de Cánovas no puede caracterizarse de tal manera. Si la España de Cánovas estuvo al margen de Europa, no fue por falta de voluntad, sino porque su falta de peso y de fiabilidad le condenaban a un forzoso aislamiento. Dos relevantes y mal conocidos ejemplos de fallidos compromisos internacionales, en 1875 y 1877, muestran elocuentemente que Cánovas sí deseaba asumir serios riesgos cuando consideraba que había importantes razones para ello. Palabras clave: Siglo XIX. Restauración. Política Exterior. Aislamiento. ABSTRACT: Spanish historiography has been considering for a long time that Cánovas foreign policy was essentially one of voluntary recogimiento (in French recueillemeni). That is a policy which implied a deliberate purpose of staying away from alliances and prominent commitments. This paper shows that Cánovas foreign policy cannot be classified as such. It was the lack of reliability and importance of Spain in the last decades of the XlXth century, that kept her isolated and away from a noticeable role in the European scene and not, by any means, the lack of will of Cánovas. The two relevant and not well known examples of failed international commitmentes which happenned in 1875 and 1877, that are examined in this article, show blatantly that Cánovas was willing to take serious international risks if he thought there were strong enough reasons to do it. Key words: XIX Century. Restoration. Foreign Policy. Isolation

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