Polyakov loop in chiral quark models at finite temperature

We describe how the inclusion of the gluonic Polyakov loop incorporates large gauge invariance and drastically modifies finite temperature calculations in chiral quark models after color neutral states are singled out. This generates an effective theory of quarks and Polyakov loops as basic degrees of freedom. We find a strong suppression of finite temperature effects in hadronic observables triggered by approximate triality conservation (Polyakov cooling), so that while the center symmetry breaking is exponentially small with the constituent quark mass, chiral symmetry restoration is exponentially small with the pion mass. To illustrate the point we compute some low energy observables at finite temperature and show that the finite temperature corrections to the low energy coefficients are $N_c$ suppressed due to color average of the Polyakov loop. Our analysis also shows how the phenomenology of chiral quark models at finite temperature can be made compatible with the expectations of chiral perturbation theory. The implications for the simultaneous center symmetry breaking-chiral symmetry restoration phase transition are also discussed.Comment: 24 pages, 8 ps figures. Figure and appendix added. To appear in Physical Review

Chiral Lagrangian at finite temperature from the Polyakov-Chiral Quark Model

We analyze the consequences of the inclusion of the gluonic Polyakov loop in chiral quark models at finite temperature. Specifically, the low-energy effective chiral Lagrangian from two such quark models is computed. The tree level vacuum energy density, quark condensate, pion decay constant and Gasser-Leutwyler coefficients are found to acquire a temperature dependence. This dependence is, however, exponentially small for temperatures below the mass gap in the full unquenched calculation. The introduction of the Polyakov loop and its quantum fluctuations is essential to achieve this result and also the correct large $N_c$ counting for the thermal corrections. We find that new coefficients are introduced at ${\cal O}(p^4)$ to account for the Lorentz breaking at finite temperature. As a byproduct, we obtain the effective Lagrangian which describes the coupling of the Polyakov loop to the Goldstone bosons.Comment: 16 pages, no figure

The Brain Network of Expectancy and Uncertainty Processing

[Background] The Stimulus Preceding Negativity (SPN) is a non-motor slow cortical potential elicited by temporally predictable stimuli, customarily interpreted as a physiological index of expectancy. Its origin would be the brain activity responsible for generating the anticipatory mental representation of an expected upcoming event. The SPN manifests itself as a slow cortical potential with negative slope, growing in amplitude as the stimulus approximates. The uncertainty hypothesis we present here postulates that the SPN is linked to control-related areas in the prefrontal cortex that become more active before the occurrence of an upcoming outcome perceived as uncertain. [Methods/Findings] We tested the uncertainty hypothesis by using a repeated measures design in a Human Contingency Learning task with two levels of uncertainty. In the high uncertainty condition, the outcome is unpredictable. In the mid uncertainty condition, the outcome can be learnt to be predicted in 75% of the trials. Our experiment shows that the Stimulus Preceding Negativity is larger for probabilistically unpredictable (uncertain) outcomes than for probabilistically predictable ones. sLoreta estimations of the brain activity preceding the outcome suggest that prefrontal and parietal areas can be involved in its generation. Prefrontal sites activation (Anterior Cingulate and Dorsolateral Prefrontal Cortex) seems to be related to the degree of uncertainty. Activation in posterior parietal areas, however, does not correlates with uncertainty. [Conclusions/Significance] We suggest that the Stimulus Preceding Negativity reflects the attempt to predict the outcome, when posterior brain areas fail to generate a stable expectancy. Uncertainty is thus conceptualized, not just as the absence of learned expectancy, but as a state with psychological and physiological entity.Research by A. Catena is funded by CONSOLIDER-INGENIO CSD2007-00012 (http://www.bcbl.eu/consolider/index.php). Research by J.C. Perales is founded by a Spanish Ministry of Science and Innovation (MICINN) grant (Dirección General de Programas y Transferencia de Conocimiento, Ref. PSI2009-13133, http://www.micinn.es/). Research by A. Catena, A. Candido, and A. Maldonado is founded by a Spanish Ministry of Science and Innovation (MICINN) grant (Dirección General de Programas y Transferencia de Conocimiento, Ref. PSI2009-12217, http://www.micinn.es/). Research was also founded by a Junta de Andalucía grant (Reference P09/SEJ-4752, http://www.juntadeandalucia.es/servicios​/ayudas/detalle/69962.html)

Influence of early romantic relationships on adolescents' sexism

The aim of this study was to analyse the influence of romantic relationships on adolescents sexism. We primed some of the participants with their past and/or present relationship experiences before assessing their sexism. A sample of 130 adolescents (67 boys and 63 girls) from Spanish high schools participated in the study. Half of them were asked to report on their relationship experience first before responding to an ambivalent sexism inventory. The other half of the sample responded first to the sexism inventory and then reported on their relationship experience. The results of this study showed that when participants relationship experiences were primed, they reported higher endorsement of sexist beliefs: boys reported higher BS and HS, whereas girls reported higher BS.El objetivo de este trabajo fue analizar la influencia que las primeras relaciones de pareja tienen en el sexismo de los y las adolescentes. Para ello, utilizamos un procedimiento que hizo salientes a algunos de los participantes sus experiencias pasadas y actuales de pareja, antes de evaluar su sexismo. Participaron en el estudio 130 adolescentes (67 chicos y 63 chicas) de centros educativos españoles. A la mitad de la muestra, se le solicitó que informaran sobre sus relaciones de pareja antes de responder a un cuestionario que medía el sexismo ambivalente. La otra mitad cumplimentó inicialmente el cuestionario de sexismo y después informó de sus relaciones de pareja. Los resultados de este estudio mostraron que al hacer salientes las relaciones de pareja, el sexismo informado por las personas participantes es mayor: en el caso de los chicos, tanto el SB como el SH, y en el caso de las chicas, el S

Flexible and Robust Privacy-Preserving Implicit Authentication

Implicit authentication consists of a server authenticating a user based on the user's usage profile, instead of/in addition to relying on something the user explicitly knows (passwords, private keys, etc.). While implicit authentication makes identity theft by third parties more difficult, it requires the server to learn and store the user's usage profile. Recently, the first privacy-preserving implicit authentication system was presented, in which the server does not learn the user's profile. It uses an ad hoc two-party computation protocol to compare the user's fresh sampled features against an encrypted stored user's profile. The protocol requires storing the usage profile and comparing against it using two different cryptosystems, one of them order-preserving; furthermore, features must be numerical. We present here a simpler protocol based on set intersection that has the advantages of: i) requiring only one cryptosystem; ii) not leaking the relative order of fresh feature samples; iii) being able to deal with any type of features (numerical or non-numerical). Keywords: Privacy-preserving implicit authentication, privacy-preserving set intersection, implicit authentication, active authentication, transparent authentication, risk mitigation, data brokers.Comment: IFIP SEC 2015-Intl. Information Security and Privacy Conference, May 26-28, 2015, IFIP AICT, Springer, to appea

Gapped continuum Kaluza-Klein spectrum

We consider a warped ve-dimensional model with an ultraviolet (UV) brane and, on top of the Standard Model isolated modes, continua of KK modes with different mass gaps for all particles: gauge bosons, fermions, graviton, radion and Higgs boson. The model can be considered as a modelization in ve dimensions of gapped unparticles. The ve dimensional metric has a singularity, at a finite (infinite) value of the proper (conformal) coordinate, which is admissible as it supports finite temperature in the form of a black hole horizon. An infrared (IR) brane, with particular jumping conditions, is introduced to trigger correct electroweak breaking. The gravitational metric is AdS5 near the UV brane, to solve the hierarchy problem with a fundamental Planck scale, and linear, in conformal coordinates, near the IR, as in the linear dilaton and ve-dimensional clockwork models. The branes, and singularity, distances are fixed, à la Goldberger-Wise, by a bulk scalar field with brane potentials explicitly breaking the conformal symmetry. The bosonic continuum of KK modes with the smallest mass gap are those of gauge bosons, and so they are the most likely produced at the LHC. Mass gaps of the continuum of KK fermions do depend on their localization in the extra dimension. We have computed the spectral functions, and arbitrary Green's functions, and shown how they can modify some Standard Model processes.The work of EM is supported by the Spanish MINEICO under Grant FIS2017-85053-C2-1-P, by the Junta de Andalucía under Grant FQM-225, by the Consejería de Conocimiento, Investigación y Universidad of the Junta de Andalucía and European Regional Development Fund (ERDF) under Grant SOMM17/6105/UGR, and by the Spanish Consolider Ingenio 2010 Programme CPAN under Grant CSD2007-00042. The research of EM is also supported by the Ramón y Cajal Program of the Spanish MINEICO under Grant RYC-2016-20678. The work of MQ is partly supported by Spanish MINEICO (Grant FPA2017-88915-P), by the Catalan Government under Grant 2017SGR1069, and by Severo Ochoa Excellence Program of MINEICO (Grant SEV-2016-0588)

Scintillator ageing of the T2K near detectors from 2010 to 2021

The T2K experiment widely uses plastic scintillator as a target for neutrino interactions and an active medium for the measurement of charged particles produced in neutrino interactions at its near detector complex. Over 10 years of operation the measured light yield recorded by the scintillator based subsystems has been observed to degrade by 0.9-2.2% per year. Extrapolation of the degradation rate through to 2040 indicates the recorded light yield should remain above the lower threshold used by the current reconstruction algorithms for all subsystems. This will allow the near detectors to continue contributing to important physics measurements during the T2K-II and Hyper-Kamiokande eras. Additionally, work to disentangle the degradation of the plastic scintillator and wavelength shifting fibres shows that the reduction in light yield can be attributed to the ageing of the plastic scintillator. The long component of the attenuation length of the wavelength shifting fibres was observed to degrade by 1.3-5.4% per year, while the short component of the attenuation length did not show any conclusive degradation.Ministerio de Ciencia e Innovación SEV-2016-0588, PID2019-107564GB-I00, PGC2018-099388-BI00European Union 713673, 754496, RISE-GA822070-JENNIFER2 2020, RISE-GA872549-SK2HKJSPS KAKENHI (JP16H06288, JP18K03682, JP18H03701, JP18H05537, JP19J01119, JP19J22440, JP19J22258, JP20H00162, JP20H00149, JP20J2030

A novel semi-fragile forensic watermarking scheme for remote sensing images

Peer-reviewedA semi-fragile watermarking scheme for multiple band images is presented. We propose to embed a mark into remote sensing images applying a tree structured vector quantization approach to the pixel signatures, instead of processing each band separately. The signature of themmultispectral or hyperspectral image is used to embed the mark in it order to detect any significant modification of the original image. The image is segmented into threedimensional blocks and a tree structured vector quantizer is built for each block. These trees are manipulated using an iterative algorithm until the resulting block satisfies a required criterion which establishes the embedded mark. The method is shown to be able to preserve the mark under lossy compression (above a given threshold) but, at the same time, it detects possibly forged blocks and their position in the whole image.Se presenta un esquema de marcas de agua semi-frágiles para múltiples imágenes de banda. Proponemos incorporar una marca en imágenes de detección remota, aplicando un enfoque de cuantización del vector de árbol estructurado con las definiciones de píxel, en lugar de procesar cada banda por separado. La firma de la imagen hiperespectral se utiliza para insertar la marca en el mismo orden para detectar cualquier modificación significativa de la imagen original. La imagen es segmentada en bloques tridimensionales y un cuantificador de vector de estructura de árbol se construye para cada bloque. Estos árboles son manipulados utilizando un algoritmo iteractivo hasta que el bloque resultante satisface un criterio necesario que establece la marca incrustada. El método se muestra para poder preservar la marca bajo compresión con pérdida (por encima de un umbral establecido) pero, al mismo tiempo, detecta posiblemente bloques forjados y su posición en la imagen entera.Es presenta un esquema de marques d'aigua semi-fràgils per a múltiples imatges de banda. Proposem incorporar una marca en imatges de detecció remota, aplicant un enfocament de quantització del vector d'arbre estructurat amb les definicions de píxel, en lloc de processar cada banda per separat. La signatura de la imatge hiperespectral s'utilitza per inserir la marca en el mateix ordre per detectar qualsevol modificació significativa de la imatge original. La imatge és segmentada en blocs tridimensionals i un quantificador de vector d'estructura d'arbre es construeix per a cada bloc. Aquests arbres són manipulats utilitzant un algoritme iteractiu fins que el bloc resultant satisfà un criteri necessari que estableix la marca incrustada. El mètode es mostra per poder preservar la marca sota compressió amb pèrdua (per sobre d'un llindar establert) però, al mateix temps, detecta possiblement blocs forjats i la seva posició en la imatge sencera

Calidad nutricional del aceite de semilla de trece especies Asphodeline (Xanthorrhoeaceae) procedentes de Turquía

The fatty acid composition of the seed oil from 13 Turkish Asphodeline species was analyzed. The seed oil content ranged between 0.9% and 4.6%, and included 26 different fatty acids from C12:0to C22:5. The most abundant saturated, monounsaturated, and polyunsaturated fatty acids were C16:0 (5.7% to 23.7% of their total fatty acid content), C18:1ω9 (11.3% to 30.3%), and C18:2ω6 (49.2% to 66.1%). A. tenuior subsp. tenuiflora, which had the highest content of unsaturated fatty acids, also had the best fatty acid profile from a nutritional point of view. Asphodeline seed oil composition was similar to that of local, related vegetables such as onion seeds. Asphodeline species, which are most frequently grown to use the leaves in salads, may also be a good source of seed oil with good nutritional properties. Results of a cluster analysis using data on the fatty acid composition are consistent with the taxonomic classification of genus Asphodeline.Se ha analizado la composición en ácidos grasos del aceite de las semillas de 13 especies de Asphodeline de Turquía. El contenido en aceite de las semillas osciló entre el 0.9% y el 4.6% e incluyó 26 ácidos grasos distintos entre C12:0y C22:5. Los ácidos grasos saturados, monoinsaturados y poliinsaturados más abundantes fueron C16:0 (5.7% a 23.7%), C18:1ω9 (11.3% a 30.3%) y C18:2ω6 (49.2% a 66.1%). A. tenuior subsp. tenuiflora, que presentó el contenido más alto en ácidos grasos insaturados, también tenía el mejor perfil en ácidos grasos desde un punto de vista nutricional. La composición del aceite de las semillas de Asphodeline fue similar a la de vegetales relacionados como la cebolla. Asphodeline, cuyas hojas son consumidas en ensaladas, puede representar también una buena fuente de aceite de las semillas con buenas propiedades nutricionales. Los resultados del análisis de grupos usando los datos de la composición en ácidos grasos son consistentes con la clasificación taxonómica del género Asphodeline

Integrate and Fire Neural Networks, Piecewise Contractive Maps and Limit Cycles

We study the global dynamics of integrate and fire neural networks composed of an arbitrary number of identical neurons interacting by inhibition and excitation. We prove that if the interactions are strong enough, then the support of the stable asymptotic dynamics consists of limit cycles. We also find sufficient conditions for the synchronization of networks containing excitatory neurons. The proofs are based on the analysis of the equivalent dynamics of a piecewise continuous Poincar\'e map associated to the system. We show that for strong interactions the Poincar\'e map is piecewise contractive. Using this contraction property, we prove that there exist a countable number of limit cycles attracting all the orbits dropping into the stable subset of the phase space. This result applies not only to the Poincar\'e map under study, but also to a wide class of general n-dimensional piecewise contractive maps.Comment: 46 pages. In this version we added many comments suggested by the referees all along the paper, we changed the introduction and the section containing the conclusions. The final version will appear in Journal of Mathematical Biology of SPRINGER and will be available at http://www.springerlink.com/content/0303-681