Assessment of Urban Subsidence in the Lisbon Metropolitan Area (Central-West of Portugal) Applying Sentinel-1 SAR Dataset and Active Deformation Areas Procedure

The Lisbon metropolitan area (LMA, central-west of Portugal) has been severely affected by different geohazards (flooding episodes, landslides, subsidence, and earthquakes) that have generated considerable damage to properties and infrastructures, in the order of millions of euros per year. This study is focused on the analysis of subsidence, as related to urban and industrial activity. Utilizing the A-DInSAR dataset and applying active deformation areas (ADA) processing at the regional scale has allowed us to perform a detailed analysis of subsidence phenomena in the LMA. The dataset consisted of 48 ascending and 61 descending SAR IW-SLC images acquired by the Sentinel-1 A satellite between January 2018 and April 2020. The line-of-sight (LOS), mean deformation velocity (VLOS) maps (mm year(-1)), and deformation time series (mm) were obtained via the Geohazard Exploitation Platform service of the European Space Agency. The maximum VLOS detected, with ascending and descending datasets, were -38.0 and -32.2 mm year(-1), respectively. ADA processing over the LMA allowed for 592 ascending and 560 descending ADAs to be extracted and delimited. From the VLOS measured in both trajectories, a vertical velocity with a maximum value of -32.4 mm year(-1) was estimated. The analyzed subsidence was associated to four ascending and three descending ADAs and characterized by maximum VLOS of -25.5 and -25.2 mm year(-1). The maximum vertical velocity associated with urban subsidence was -32.4 mm year(-1). This subsidence is mainly linked to the compaction of the alluvial and anthropic deposits in the areas where urban and industrial sectors are located. The results of this work have allowed to: (1) detect and assess, from a quantitative point of view, the subsidence phenomena in populated and industrial areas of LMA; (2) establish the relationships between the subsidence phenomena and geological and hydrological characteristics.Programa de Apoyo y Promocion a la Investigacion 2021 at University of Oviedo PAPI-21-PF-22Project SLIDE-APCR FUO-21-069European Regional Development Fund (ERDF) through the project RISKCOAST of the Interreg SUDOE Programme SOE3/P4/E086

Measurement of net electric charge and dipole moment of dust aggregates in a complex plasma

Understanding the agglomeration of dust particles in complex plasmas requires a knowledge of the basic properties such as the net electrostatic charge and dipole moment of the dust. In this study, dust aggregates are formed from gold coated mono-disperse spherical melamine-formaldehyde monomers in a radio-frequency (rf) argon discharge plasma. The behavior of observed dust aggregates is analyzed both by studying the particle trajectories and by employing computer models examining 3D structures of aggregates and their interactions and rotations as induced by torques arising from their dipole moments. These allow the basic characteristics of the dust aggregates, such as the electrostatic charge and dipole moment, to be determined. It is shown that the experimental results support the predicted values from computer models for aggregates in these environments.Comment: 6 pages, 7 figure

La colección de impresos de tipografía portuguesa del siglo XVI de la Universidad Complutense de Madrid.

Sin resume

Reacción en cadena de la polimerasa para la detección de Streptococcus mutans y Streptococcus sobrinus en placa dental de preescolares de Cartagena, Colombia.

Objectives: To detect the presence of Streptococcus mutans and Streptococcus sobrinus in dental plaque of children from Cartagena and correlate it to dental caries precavity stages, applying a standardized PCR-based technique for epidemiological purposes. Methods: Descriptive study using a non-probabilistic sample of 50 children between 3 and 5 years of age, preschoolers from a Caribbean population in Colombia. Criteria for selection were that children should exhibit plaque accumulations on the surface of the cervical margins of the rearmost molars, and placed in one of two study groups: carious lesions and sound surfaces. Dental plaque samples from both groups were subjected to molecular analysis and statistical analysis was applied to determine the difference between the two groups using the frequencies of presence of S. mutans, S. sobrinus or both in the two groups applying Fisher’s exact test for association between the presence of microorganisms and the state of the tooth surface from where the dental plaque was taken. Results: The frequency of S. mutans in carious lesions was 76% and 24% in healthy surfaces. The frequency of S. sobrinus in carious lesions was 81.9% and 18.1% in caries-free surfaces. There was statistical significance between the presence of S. mutans and the presence of caries (p=0.001) and between the presence of S. sobrinus (p=0.02) and the presence of caries. There was no statistical significance between the presence of caries and the simultaneous presence of both microorganisms (p=0.08). Conclusions: The presence of S. mutans and S. sobrinus in dental plaque samples is highly prevalent and associated to non cavitated carious lesions, being the molecular identification of these microorganisms by PCR a sensitive, fast, and easy to use detection method for the mutans group of oral bacteria. Objetivos: Detectar la presencia de Streptococcus mutans y Streptococcus sobrinus en placa dental de niños de Cartagena y relacionarlo con la caries dental en estadíos precavitacionales, estandarizándose la técnica basada en PCR para detectar a nivel epidemiológico la presencia de estos microorganismos. Métodos: Estudio de tipo descriptivo, a partir de una muestra no probabilística de 50 niños entre 3 y 5 años de los hogares infantiles de una población del Caribe colombiano. Como criterios de selección se tuvo en cuenta que los niños presentaran acumulaciones de placa dental sobre la superficie de los márgenes cervicales de los últimos molares. El estudio se dividió en dos grupos: lesiones cariosas y superficies sanas. Las mediciones se realizaron a partir de muestras de placa dental, sometidas a análisis molecular. El análisis estadístico se realizó a partir de las frecuencias de presencia de S. mutans, S. sobrinus o ambos en las lesiones cariosas y superficies sanas, utilizando la prueba exacta de Fisher para la asociación entre la presencia de los microorganismos y el estado de la superficie dental donde se encontró la placa. Resultados: La frecuencia de S. mutans para las lesiones cariosas fue 76% y 24% en superficies sanas. Con respecto a S. sobrinus, la frecuencia en lesiones cariosas fue 81.9% y 18.1% en superficies sin caries. La presencia de caries estuvo asociada significativamente en forma individual con S. mutans (p=0.001) o con S. sobrinus (p=0.02), pero no fue significante con la presencia simultánea de los dos microorganismos (p=0.08). Conclusiones: La presencia de S. mutans y S. sobrinus en muestras de placa bacteriana se considera un factor de asociación con la presencia de lesiones de caries precavitacionales, siendo la identificación molecular por PCR un método sensible, rápido y de fácil uso para la detección de bacterias del grupo mutans

Time delays, choice of energy-momentum variables, and relative locality in doubly special relativity

Doubly special relativity (DSR) theories consider (quantum-gravity motivated) deformations of the symmetries of special relativity compatible with a relativity principle. The existence of time delays for massless particles, one of their proposed phenomenological consequences, is a delicate question since, contrary to what happens with Lorentz invariance violation scenarios, they are not simply determined by the modification in the particle dispersion relation. While some studies of DSR assert the existence of photon time delays, in this paper we generalize a recently proposed model for time delay studies in DSR and show that the existence of photon time delays does not necessarily follow from a DSR scenario, determining in which cases this is so. Moreover, we clarify long-standing questions about the arbitrariness in the choice of the energy-momentum labels and the independence of the time delay on this choice, as well as on the consistency of its calculation with the relative locality paradigm of DSR theories. Finally, we show that the result for time delays is reproduced in models that consider propagation in a noncommutative spacetime

Ants (Hymenoptera: Formicidae) as surrogates for epigeic arthropods in Northern Andalusian ‘dehesas’ (Spain)

The ‘dehesas’ are important and vast agro-silvo-pastoral systems typical of the Iberian Peninsula that are undergoing a crisis due to their low economic profitability and environmental degradation. Thus, it is necessary to identify effective tools that provide a reliable idea of the status of these ecosystems as a starting point for future measures of conservation. In this study we analyse the possible role of ants as surrogates for epigeic arthropods, a common biodiversity indicator group. A total of 15 farms were sampled throughout Sierra Morena (Andalusia, Spain) with pitfall traps, both for the ‘dehesa’ habitats themselves and for different microhabitats within the study sites. First, we achieve a complete list of the species of ants of the area. The results indicate that the ‘dehesa’ habitats were very homogenous for all farms, while microhabitats showed differences in species richness and ant communities’ composition compared to the ‘dehesas’. To evaluate the role of ants as surrogates, the number of traps occupied by each order of arthropod and by each ant species was compared. We found a high correlation between them what confirm the surrogate character of ants for the rest of arthropods in these ecosystems

Consistency of Lorentz-invariance violation neutrino scenarios in time delay analyses

Modifications inspired by quantum gravity in the kinematics of special relativity can manifest in various ways, including anomalies in the time of flight of massless particles and the emergence of decay channels for otherwise stable particles. Typically, these effects are studied independently; however, it may be necessary to combine both to perform a consistent analysis. In this work, we study the interplay between time-of-flight anomalies and neutrino instability in the context of a flavor-independent high-energy Lorentz-invariance violation (LIV) in the neutrino sector. Ensuring compatibility between both types of effects imposes strong constraints on the existence of early neutrinos with energies exceeding a maximum value determined by the scale of new physics. Such constraints depend on the specific LIV scenario and should be integrated into searches for high-energy neutrinos from gamma-ray bursts exhibiting LIV time shifts.Comment: 14 pages, 6 figure