Cosmic magnetic fields and dark energy in extended electromagnetism

We discuss an extended version of electromagnetism in which the usual gauge fixing term is promoted into a physical contribution that introduces a new scalar state in the theory. This new state can be generated from vacuum quantum fluctuations during an inflationary era and, on super-Hubble scales, gives rise to an effective cosmological constant. The value of such a cosmological constant coincides with the one inferred from observations as long as inflation took place at the electroweak scale. On the other hand, the new state also generates an effective electric charge density on sub-Hubble scales that produces both vorticity and magnetic fields with coherent lengths as large as the present Hubble horizon.Comment: 4 pages, 2 figures. Contribution to the proceedings of Spanish Relativity Meeting 2010, Granada, Spain, 6-10 September 201

Perturbations in electromagnetic dark energy

It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological constant and therefore, the homogeneous cosmology produced by such a model is exactly the same as that of $\Lambda$CDM. However, unlike a cosmological constant term, electromagnetic fields can acquire perturbations which in principle could affect CMB anisotropies and structure formation. In this work, we study the evolution of inhomogeneous scalar perturbations in this model. We show that provided the initial electromagnetic fluctuations generated during inflation are small, the model is perfectly compatible with both CMB and large scale structure observations at the same level of accuracy as $\Lambda$CDM.Comment: 12 pages, 3 figures. Added new comments to match the published versio

The Dark Magnetism of the Universe

Despite the success of Maxwell's electromagnetism in the description of the electromagnetic interactions on small scales, we know very little about the behaviour of electromagnetic fields on cosmological distances. Thus, it has been suggested recently that the problems of dark energy and the origin of cosmic magnetic fields could be pointing to a modification of Maxwell's theory on large scales. Here, we review such a proposal in which the scalar state which is usually eliminated be means of the Lorenz condition is allowed to propagate. On super-Hubble scales, the new mode is essentially given by the temporal component of the electromagnetic potential and contributes as an effective cosmological constant to the energy-momentum tensor. The new state can be generated from quantum fluctuations during inflation and it is shown that the predicted value for the cosmological constant agrees with observations provided inflation took place at the electroweak scale. We also consider more general theories including non-minimal couplings to the space-time curvature in the presence of the temporal electromagnetic background. We show that both in the minimal and non-minimal cases, the modified Maxwell's equations include new effective current terms which can generate magnetic fields from sub-galactic scales up to the present Hubble horizon. The corresponding amplitudes could be enough to seed a galactic dynamo or even to account for observations just by collapse and differential rotation in the protogalactic cloud.Comment: Invited brief review to appear in Modern Physics Letters

The Influence of Patient Experience with Healthcare on the Health-Related Quality of Life of People Living with HIV: An Observational Cross-Sectional Survey

[Abstract] Introduction Patient experience is central to the quality of healthcare delivery, showing positive associations with several outcome measures. The main objectives of this study are to analyze the influence of patient experience on the health-related quality of life in people living with HIV and the role played by treatment complexity and clinical care. Methods We conducted a cross-sectional survey with 467 patients with HIV. We used the Instrument for Evaluation of the Experience of Chronic Patients and the Health-related Quality of Life Questionnaire (EQ-5D-5L). We analyzed a predictive model through the partial least squares (PLS) method. Results The patient self-management scores showed the highest positive relationship with the patient’s health-related quality of life (β = 0.24, β = 0.32, p  50 years old (p < 0.05). Conclusions Patient experience mainly influenced the health-related quality of life of older people living with HIV. The treatment and clinical care complexity played an important role in degrading the patients' experience and their quality of life. More integrated care would benefit the health-related quality of life of people living with HIV

Focusing of geodesic congruences in an accelerated expanding Universe

We study the accelerated expansion of the Universe through its consequences on a congruence of geodesics. We make use of the Raychaudhuri equation which describes the evolution of the expansion rate for a congruence of timelike or null geodesics. In particular, we focus on the space-time geometry contribution to this equation. By straightforward calculation from the metric of a Robertson-Walker cosmological model, it follows that in an accelerated expanding Universe the space-time contribution to the Raychaudhuri equation is positive for the fundamental congruence, favoring a non-focusing of the congruence of geodesics. However, the accelerated expansion of the present Universe does not imply a tendency of the fundamental congruence to diverge. It is shown that this is in fact the case for certain congruences of timelike geodesics without vorticity. Therefore, the focusing of geodesics remains feasible in an accelerated expanding Universe. Furthermore, a negative contribution to the Raychaudhuri equation from space-time geometry which is usually interpreted as the manifestation of the attractive character of gravity is restored in an accelerated expanding Robertson-Walker space-time at high speeds.Comment: 11 pages, 2 figures. Final version changed to match published version in JCAP. References updated. Conclusions unchange

Mutation in the FUS nuclear localisation signal domain causes neurodevelopmental and systemic metabolic alterations

Variants in the ubiquitously expressed DNA/RNA-binding protein FUS cause aggressive juvenile forms of amyotrophic lateral sclerosis (ALS). Most FUS mutation studies have focused on motor neuron degeneration; little is known about wider systemic or developmental effects. We studied pleiotropic phenotypes in a physiological knock-in mouse model carrying the pathogenic FUSDelta14 mutation in homozygosity. RNA sequencing of multiple organs aimed to identify pathways altered by the mutant protein in the systemic transcriptome, including metabolic tissues, given the link between ALS-frontotemporal dementia and altered metabolism. Few genes were commonly altered across all tissues, and most genes and pathways affected were generally tissue specific. Phenotypic assessment of mice revealed systemic metabolic alterations related to the pathway changes identified. Magnetic resonance imaging brain scans and histological characterisation revealed that homozygous FUSDelta14 brains were smaller than heterozygous and wild-type brains and displayed significant morphological alterations, including a thinner cortex, reduced neuronal number and increased gliosis, which correlated with early cognitive impairment and fatal seizures. These findings show that the disease aetiology of FUS variants can include both neurodevelopmental and systemic alterations

Desarrollo de productos avanzados para la misión SEOSAT/Ingenio

Revista oficial de la Asociación Española de Teledetección[EN] SEOSAT/Ingenio is the future Spanish Earth Observation high spatial resolution mission in the optical domain. While Level 1 products, at-sensor geo-referenced radiances, are in an advanced phase of development under the framework of an industrial contractor, Level 2 products must be developed by the users. This fact limits the use of the satellite images only to the scientific community, restricting their use in other applications. The need to alleviate this limitation motivated this work, developed under the framework of a coordinate project, which aimed at offering a list of Level2 products to the Ingenio/SEOSAT user community. In this paper, we present the different methodologies developed to produce the proposed Level2 products, from surface reflectance at nominal sensor spatial resolution to images with higher spatial resolution or the possibility to create spatial and temporal mosaics. On the one side, for the surface reflectance product, we proposed an atmospheric correction algorithm based on using the spatial information, linked to a cloud screening algorithm and including morphological and topographic shadow corrections. On the other side, to enhance the image spatial resolution, we applied different fusion techniques using the multispectral and the panchromatic band, as well as some of the so-called “super-resolution” techniques. Finally, we provided different tools to develop spatial mosaics and temporal composites, directed to users interested on the exploitation of the Ingenio/ SEOSAT images.[ES] SEOSAT/Ingenio es la futura misión española de observación de la Tierra en el óptico en alta resolución es-pacial. Mientras que los productos de imagen a Nivel 1, radiancias geo-referenciadas a nivel de sensor, se encuentran en una fase avanzada de desarrollo existiendo para ello un contrato industrial, los productos de Nivel 2 deben ser de-sarrollados por los propios usuarios. Este hecho limita el uso de las imágenes a la comunidad científica, restringiendo sus posibles aplicaciones fuera de ésta. Así pues, bajo el marco de un proyecto coordinado y motivados por ofrecer productos de Ingenio/SEOSAT de Nivel 2 a disposición de cualquier usuario, se origina y desarrolla este trabajo. En este artículo se presentan los diferentes procesos desarrollados para la elaboración de productos a Nivel 2, desde reflectividades en superficie a la resolución nominal del sensor hasta imágenes con información espacial realzada y la posibilidad de crear mosaicos espaciales y compuestos temporales. Por una parte, en el caso de los productos de reflectividad en superficie se propone una técnica de corrección atmosférica basada en el uso de la información es-pacial, previo enmascaramiento de las nubes y una exhaustiva corrección de sombras morfológicas y/o topográficas. Por otra parte, para el realce de la información espacial, han sido evaluados diferentes métodos basados en la fusión de bandas multiespectrales con una banda pancromática así como la aplicación de técnicas llamadas de “Super-re-solución”. Finalmente, se proporcionan las herramientas necesarias para la realización de mosaicos tanto espaciales como temporales para todo tipo de usuarios interesados en la explotación de las imágenesEste artículo ha sido posible gracias al proyecto coordinado “Generación de Productos de Nivel 2 para la Misión INGENIO/SEOSAT”, ESP2013- 48458-C4-1-P, subvencionado por el Ministerio de Economia y Competitividad dentro del Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia.Sabater, N.; Ruiz-Verdú, A.; Delegido, J.; Fernández-Beltrán, R.; Latorre-Carmona, P.; Pla, F.; González-Audícana, M.... (2016). Development of advanced products for the SEOSAT/Ingenio mission. Revista de Teledetección. (47):23-40. https://doi.org/10.4995/raet.2016.6569SWORD234047Blesius, L., & Weirich, F. (2005). The use of the Minnaert correction for land‐cover classification in mountainous terrain. 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Block Adjustment of High-Resolution Satellite Images Described by Rational Polynomials. Photogrammetric Engineering & Remote Sensing, 69(1), 59-68. doi:10.14358/pers.69.1.59Liu, J. G. (2000). Smoothing Filter-based Intensity Modulation: A spectral preserve image fusion technique for improving spatial details. International Journal of Remote Sensing, 21(18), 3461-3472. doi:10.1080/014311600750037499Marini, A., Reina Barragan, F.J., Crippa, G., Harnisch, B., Fuente, I., Lopez, M., Cabeza, I., Zorita, D. 2014. SEOSAT/INGENIO – A Spanish High-spatial-resolution optical mission. International Conference on Space Optics. Tenerife, Spain, 7-10 octubre.Mekler, Y., & Kaufman, Y. J. (1982). Contrast reduction by the atmosphere and retrieval of nonuniform surface reflectance. Applied Optics, 21(2), 310. doi:10.1364/ao.21.000310Otazu, X., Gonzalez-Audicana, M., Fors, O., & Nunez, J. (2005). Introduction of sensor spectral response into image fusion methods. Application to wavelet-based methods. 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Walker-Warburg syndrome

Walker-Warburg Syndrome (WWS) is a rare form of autosomal recessive congenital muscular dystrophy associated with brain and eye abnormalities. WWS has a worldwide distribution. The overall incidence is unknown but a survey in North-eastern Italy has reported an incidence rate of 1.2 per 100,000 live births. It is the most severe form of congenital muscular dystrophy with most children dying before the age of three years. WWS presents at birth with generalized hypotonia, muscle weakness, developmental delay with mental retardation and occasional seizures. It is associated with type II cobblestone lissencephaly, hydrocephalus, cerebellar malformations, eye abnormalities and congenital muscular dystrophy characterized by hypoglycosylation of α-dystroglycan. Several genes have been implicated in the etiology of WWS, and others are as yet unknown. Several mutations were found in the Protein O-Mannosyltransferase 1 and 2 (POMT1 and POMT2) genes, and one mutation was found in each of the fukutin and fukutin-related protein (FKRP) genes. Laboratory investigations usually show elevated creatine kinase, myopathic/dystrophic muscle pathology and altered α-dystroglycan. Antenatal diagnosis is possible in families with known mutations. Prenatal ultrasound may be helpful for diagnosis in families where the molecular defect is unknown. No specific treatment is available. Management is only supportive and preventive

Effectiveness of habitat management in the recovery of low-density populations of wild rabbit.

Understanding the relationship between spatial patterns of landscape attributes and population presence and abundance is essential for understanding population processes as well as supporting management and conservation strategies. This study evaluates the influence of three factors: environment, habitat management, and season on the presence and abundance of the wild rabbit (Oryctolagus cuniculus), an important prey species for Mediterranean endangered predator species. To address this issue, we estimated wild rabbit presence and abundance by latrine counting in transects located in 45 plots within a 250×250 m grid from June 2007 until June 2009 in a 1,200 ha hunting area in southern Portugal.We then analyzed how wild rabbit presence and abundance correlatewith the aforementioned factors. Our results showed that the main variable influencing wild rabbit presence and abundance was the distance to the artificial warrens. North and northeast slope directions were negatively related to wild rabbit presence. Conversely, rabbit presence was positively correlated with short distances to ecotone, artificial warrens, and spring. Regarding rabbit abundance, in addition to artificial warrens, soft soils, bushes, and season also had a positive effect. We found that environmental variables, management practices, and season each affect wild rabbit presence and abundance differently at a home range scale in low-density population. Thus, our major recommendations are reducing the distance to artificial warrens and ecotone, ideally to less than 100 m, and promoting habitat quality improvement on slopes with plenty of sun exposure

COL4A1 Mutations Cause Ocular Dysgenesis, Neuronal Localization Defects, and Myopathy in Mice and Walker-Warburg Syndrome in Humans

Muscle-eye-brain disease (MEB) and Walker Warburg Syndrome (WWS) belong to a spectrum of autosomal recessive diseases characterized by ocular dysgenesis, neuronal migration defects, and congenital muscular dystrophy. Until now, the pathophysiology of MEB/WWS has been attributed to alteration in dystroglycan post-translational modification. Here, we provide evidence that mutations in a gene coding for a major basement membrane protein, collagen IV alpha 1 (COL4A1), are a novel cause of MEB/WWS. Using a combination of histological, molecular, and biochemical approaches, we show that heterozygous Col4a1 mutant mice have ocular dysgenesis, neuronal localization defects, and myopathy characteristic of MEB/WWS. Importantly, we identified putative heterozygous mutations in COL4A1 in two MEB/WWS patients. Both mutations occur within conserved amino acids of the triple-helix-forming domain of the protein, and at least one mutation interferes with secretion of the mutant proteins, resulting instead in intracellular accumulation. Expression and posttranslational modification of dystroglycan is unaltered in Col4a1 mutant mice indicating that COL4A1 mutations represent a distinct pathogenic mechanism underlying MEB/WWS. These findings implicate a novel gene and a novel mechanism in the etiology of MEB/WWS and expand the clinical spectrum of COL4A1-associated disorders