Electromagnetic quasinormal modes of five-dimensional topological black holes

We calculate exactly the QNF of the vector type and scalar type electromagnetic fields propagating on a family of five-dimensional topological black holes. To get a discrete spectrum of quasinormal frequencies for the scalar type electromagnetic field we find that it is necessary to change the boundary condition usually imposed at the asymptotic region. Furthermore for the vector type electromagnetic field we impose the usual boundary condition at the asymptotic region and we discuss the existence of unstable quasinormal modes in the five-dimensional topological black holes.Comment: 16 pages. Already published in Revista Mexicana de Fisic

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Synchronization and Diversity in Business Cycles: A Network Approach Applied to the European Union

This paper analyses synchronization in business cycles across the European Union (EU) since 1989. We include both old and new European Union members and countries which are currently negotiating accession, as well as potential European Union members. Our methodological approach is based on the correlation matrix and the networks within, which allows us to summarize the individual interaction and co-movement, while also capturing the existing heterogeneity of connectivity within the European economic system. The results indicate that the synchronization of the old EU countries remained stable until the current financial crisis. Additionally, the synchronization of the new and potential members has approached to the old EU members although we observe the existence of different synchronization levels and dynamics in output growth in single countries as well as in groups of countries. Some countries have achieved an important degree of co-movement (such as the Baltic Republics, Hungary, Slovenia and Iceland), while others have experienced reduced synchronization, or even desynchronization (such as Romania, Bulgaria and even Greece and Ireland).Business cycle synchronization, European Union countries, EU candidates, complex systems, network topology.

Measuring Globalization: A hierarchical network approach

This paper investigates the business cycle co-movement across countries and regions since the middle of the last century as a measure for quantifying the ongoing globalization process of the world economy. Our methodological approach is based on analysis of a correlation matrix and the networks it contains. Such an approach summarizes the interaction and interdependence of all elements and it represents a more accurate measure of the global interdependence involved in the economic system. Our results show (1) that the dynamics of globalization has been more driven by synchronization in regional growth patterns than by the synchronization of the world economy as a whole in contrast with other empirical works and (2) that world crisis periods increase dramatically the global co movement in the world economy.Globalization, regionalism, correlation matrix, clustering, synchronization

Biometric presentation attack detection: beyond the visible spectrum

The increased need for unattended authentication in multiple scenarios has motivated a wide deployment of biometric systems in the last few years. This has in turn led to the disclosure of security concerns specifically related to biometric systems. Among them, presentation attacks (PAs, i.e., attempts to log into the system with a fake biometric characteristic or presentation attack instrument) pose a severe threat to the security of the system: any person could eventually fabricate or order a gummy finger or face mask to impersonate someone else. In this context, we present a novel fingerprint presentation attack detection (PAD) scheme based on i) a new capture device able to acquire images within the short wave infrared (SWIR) spectrum, and i i) an in-depth analysis of several state-of-theart techniques based on both handcrafted and deep learning features. The approach is evaluated on a database comprising over 4700 samples, stemming from 562 different subjects and 35 different presentation attack instrument (PAI) species. The results show the soundness of the proposed approach with a detection equal error rate (D-EER) as low as 1.35% even in a realistic scenario where five different PAI species are considered only for testing purposes (i.e., unknown attacks

Co-movements in commodity prices: a note based on network analysis

This paper analyses co-movements in a wide group of commodity prices during the time period 1992-2010. Our methodological approach is based on the correlation matrix and the networks inside. Through this approach we are able to summarize global interaction and interdependence, capturing the existing heterogeneity in the degrees of synchronization between commodity prices. Our results produce two main findings: (a) we do not observe a persistent increase in the degree of co-movement of the commodity prices in our time sample, however from mid-2008 to the end of 2009 co-movements almost doubled when compared with the average correlation; (b) we observe three groups of commodities which have exhibited similar price dynamics (metals, oil and grains and oilseeds) and which have increased their degree of co-movement during the sampled period. These results suggest that speculation and uncertainty are drivers of the sharp slump in commodity prices synchronization.commodity prices, co-movement, hierarchy and topology, networks, complex systems

Kinematic and physiological analysis of the performance of the referee football and its relationship with decision making

The aim of this study was to examine the cinematic and physiological requirements of referees and assistant referees and their relationship to decision-making in various official competition matches in football. The sample consisted of six referees, one acted as main referee and five as assistant referees (age: 21.2 ± 0.98 years; height: 175.67 ± 4.27 cm, weight: 65.73 ± 4.68 kg). The registration of the data of the subjects participating in the study was conducted with an inertial system called WIMU and the analysis of the data was performed with a software called Quiko (RealTrack Systems, Almeria, Spain). In the study, 4 games of the League Championship Third Division (Group XIII) belonging to the 2014-2015 season were analyzed. The main findings were that the referee runs an average distance of 10124.7 ± 543.2 meters, with an average speed between 7.2 and 13 km/h with a maximum heart rate (HRmax) between 85-95% of his maximum; assistant referees walked an average distance of 5793.4 ± 481.7 meters, with an average speed between 3.6 to 7.2 km/h with a HRmax between 75-85% of their maximum. The aspects which influenced the decision making of the referees and caused the errors were: the part of the pitch, the period of play and the HRmax percentage of the referee. What this research shows is that referees and assistant referees should be considered in terms of training as independent people, and that referees must correct the movements in the field, concentration and work situations where your HRmax is above 85% to improve its success rate. Future studies should pursue this investigation with a greater number of senior officials and higher number of matches to generalize the results to all arbitral establishments and improve its quality

Resolution of inflammation: an integrated view

O.S. is supported by the NWO (VIDI project 91712303), theDFG (SO876/3-1, SO876/6-1, FOR809, SFB914 TPB08), theGerman-Israeli Foundation, and the Else Kro¨ner FreseniusStiftung. M.P. is supported by the Wellcome Trust (program086867/Z/08), the Arthritis Research UK, the British HeartFoundation (PG/09/060 and PG/11/48/28981) and the MedicalResearch Council