Dynamics of Interacting Quintessence Models: Observational Constraints

Interacting quintessence models have been proposed to explain or, at least, alleviate the coincidence problem of late cosmic acceleration. In this paper we are concerned with two aspects of these kind of models: (i) the dynamical evolution of the model of Chimento et al. [L.P. Chimento, A.S. Jakubi, D. Pavon, and W. Zimdahl, Phys. Rev. D 67, 083513 (2003).], i.e., whether its cosmological evolution gives rise to a right sequence of radiation, dark matter and dark energy dominated eras, and (ii) whether the dark matter dark energy ratio asymptotically evolves towards a non-zero constant. After showing that the model correctly reproduces these eras, we correlate three data sets that constrain the interaction at three redshift epochs: $z\le 10^{4}$, $z=10^{3}$, and $z=1$. We discuss the model selection and argue that even if the model under consideration fulfills both requirements, it is heavily constrained by observation. The prospects that the coincidence problem can be explained by the coupling of dark matter to dark energy are not clearly favored by the data.Comment: 16 pages, 7 figures and 3 tables. Modifications introduced to match published versio

Propuesta didáctica basada en la programación neuro lingüística, encaminada al mejoramiento de las falencias ortográficas de los alumnos de un Colegio Público de Bogotá.

La intención fundamental del presente proyecto, es utilizar la teoría propuesta por la programación neurolingüística (PNL) para el mejoramiento de la memoria visual como método en la construcción de la ortografía. Diseñar una propuesta didáctica que permita a los estudiantes una nueva herramienta del estudio en dicho campo. La ausencia de metodologías para el estudio de la ortografía lleva a que los docentes recurran a métodos tradicionales que no tienen en cuenta las últimas investigaciones en materia cognitiva, pues los métodos tradicionales se basan es en la memorización de palabras y reglas

Limits on the parameters of the equation of state for interacting dark energy

Under the assumption that cold dark matter and dark energy interact with each other through a small coupling term, $Q$, we constrain the parameter space of the equation of state $w$ of those dark energy fields whose variation of the field since last scattering do not exceed Planck's mass. We use three parameterizations of $w$ and two different expressions for $Q$. Our work extends previous ones.Comment: 18 pages, 11 figures, accepted for publication on Physics Letters

Public Security Strategies and their Impact on the Economic Field

La función de la promoción de la seguridad pública desempeña rol esencial que fortalece el respaldo del desarrollo de la economía y en al ámbito social. Conforme a que la policía realice su labor de manera eficiente, se identificará una percepción social adecuada y se presentarán alternativas claras y objetivas que garanticen el desarrollo económico del entorno. Por lo anterior, este estudio se centró en examinar las tácticas desarrolladas por los empresarios de Chetumal con el fin de potenciar el rendimiento de las iniciativas de protección ciudadana, con la meta de impulsar el progreso económico y el bienestar en la localidad, se enfoca en la determinación de escenarios adecuados para el fomento económico en un entorno donde la seguridad esté garantizada y que exista confianza en los cuerpos policiales, lo cual, a partir de un estudio etnográfico, se entrevistaron a diversos comerciantes de la capital del estado para conocer su percepción respecto a la seguridad y sus aportaciones para la definición de estrategias relevantes, donde el fomento a la colaboración, el enfoque de prevención, el mejoramiento de infraestructura y la promoción de la participación ciudadana fueron los pilares sustanciales en las aportaciones que brindaron viabilidad para la definición de las propuestas determinadas en esta indagatoria.The function of promoting public security plays an essential role that strengthens support for the development of the economy and the social sphere. As the police carry out their work efficiently, an adequate social perception will be identified and clear and objective alternatives will be presented that guarantee the economic development of the environment. Therefore, this study focused on examining the tactics developed by Chetumal businessmen in order to enhance the performance of citizen protection initiatives, with the goal of promoting economic progress and well-being in the town, focusing on the determination of appropriate scenarios for economic development in an environment where security is guaranteed and there is trust in the police forces, which, based on an ethnographic study, various merchants in the state capital were interviewed to know their perception regarding security and its contributions to the definition of relevant strategies, where the promotion of collaboration, the prevention approach, the improvement of infrastructure and the promotion of citizen participation were the substantial pillars in the contributions that provided viability for the definition of the proposals determined in this investigation

Sibsonian and non-Sibsonian natural neighbour interpolation of the total electron content value

In radioastronomy the interferometric measurement between radiotelescopes located relatively close to each other helps removing ionospheric effects. Unfortunately, in case of networks such as LOw Frequency ARray (LOFAR), due to long baselines (currently up to 1500 km), interferometric methods fail to provide sufficiently accurate ionosphere delay corrections. Practically it means that systems such as LOFAR need external ionosphere information, coming from Global or Regional Ionospheric Maps (GIMs or RIMs, respectively). Thanks to the technology based on Global Navigation Satellite Systems (GNSS), the scientific community is provided with ionosphere sounding virtually worldwide. In this paper we compare several interpolation methods for RIMs computation based on scattered Vertical Total Electron Content measurements located on one thin ionospheric layer (Ionospheric Pierce Points—IPPs). The results of this work show that methods that take into account the topology of the data distribution (e.g., natural neighbour interpolation) perform better than those based on geometric computation only (e.g., distance-weighted methods).Peer ReviewedPostprint (published version

Ionospheric tomographic common clock model of undifferenced uncombined GNSS measurements

This is a post-peer-review, pre-copyedit version of an article published in Journal of geodesy. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00190-021-01568-8In this manuscript, we introduce the Ionospheric Tomographic Common Clock (ITCC) model of undifferenced uncombined GNSS measurements. It is intended for improving the Wide Area precise positioning in a consistent and simple way in the multi-GNSS context, and without the need of external precise real-time products. This is the case, in particular, of the satellite clocks, which are estimated at the Wide Area GNSS network Central Processing Facility (CPF) referred to the reference receiver one; and the precise realtime ionospheric corrections, simultaneously computed under a voxel-based tomographic model with satellite clocks and other geodetic unknowns, from the uncombined and undifferenced pseudoranges and carrier phase measurements at the CPF from the Wide Area GNSS network area. The model, without fixing the carrier phase ambiguities for the time being (just constraining them by the simultaneous solution of both ionospheric and geometric components of the uncombined GNSS model), has been successfully applied and assessed against previous precise positioning techniques. This has been done by emulating real-time conditions for Wide Area GPS users during 2018 in Poland.Peer ReviewedPostprint (published version

Fat–Fit Patterns, Drug Consumption, and Polypharmacy in Older Adults: The EXERNET Multi-Center Study

[EN] Background: Physical fitness levels and the amount of accumulated adipose tissue (fatness) relate to current and future individuals’ heath status. Nevertheless, the interrelationships of their combined patterns with polypharmacy and the types of medications consumed have not been sufficiently investigated. Methods: This cross-sectional study was carried out in six Spanish regions between 2008 and 2009 with a sample of older community-dwelling adults (≥ 65 years old) without dementia or cancer. Fitness was measured with one-leg balance and senior fitness tests, as well as by measuring weight and fat mass with a bioelectrical impedance analyzer. Polypharmacy was defined as the use of five or more medications. An analysis of variance was performed for comparisons between the physical fitness and fatness patterns and the medication consumed. Results: A total of 1709 elders were included in the study (72.1 ± 5.2 years). The two unfit patterns were those with the highest drug consumption. The High-Fat–Unfit pattern was the one that had the most significant consumption and had the highest percentage of polymedicated subjects. The Low-Fat–Fit pattern had a significantly lower percentage of people that did not consume any medications. The highest percentages of drug consumption in 7 of the 10 groups that were included were concentrated in the two unfit patterns. Conclusions: This study highlights the importance of fitness in older adults, as it is at least as important as the avoidance of accumulation of excess fat with respect to the consumption of a smaller number of medicines.S

Evaluación de la acción antiséptica de un jabón líquido utilizando algunos aceites esenciales como agente activo

Se evaluó la acción antiséptica de un jabón líquido utilizando como activo aceitesesenciales de Eugenia caryophyllata T. (clavo de olor) y Cinnamomum verum J.(canela). Se formularon y elaboraron jabones líquidos usando como activo aceitesesenciales a concentraciones de 1,5% y 2%, posteriormente se evaluaron parámetrosfisicoquímicos, sensoriales, así como también microbiológicos sobre cepas bacterianasde Escherichia coli ATCC 25922 y Staphylococcus aureus ATCC 25923. Se encontróque las formulaciones idóneas son aquellas en las que los aceites esenciales de clavo ycanela se encuentran a concentraciones del 2%, puesto que presentan actividad contralas cepas bacterianas en cuestión y mejor estabilidad fisicoquímica; siendo elegidoentre los evaluadores de las propiedades organolépticas el jabón líquido preparadocon aceite esencial de canela como el favorito con respecto al de clavo, por presentar mejor aroma y aspecto. Se concluye que los jabones líquidos antisépticos a partir de 2%de aceite esencial de Eugenia caryophyllata T. y Cinnamomum verum J. presentaronresultados promisorios; igualmente, todos los indicadores fisicoquímicos y químicosevaluados se mantuvieron, lo que nos brinda un indicio de la correcta formulacióndesde el punto de vista galénic.The antiseptic action of a liquid soap was evaluated using as essential oils of Eugeniacaryophyllata T. (clove) and Cinnamomum verum J. (cinnamon). Is formulated andproduced soaps liquids using as active oils essential to concentrations of 1.5% and 2%,subsequently is evaluated parameters physicochemical, sensory, as well as also microbiologicalon strains bacterial of Escherichia coli ATCC 25922 and Staphylococcusaureus ATCC 25923. Finding is that the formulations suitable are those in whichthem oils essential of clove and cinnamon is found to concentrations of the 2%, sincepresent activity against them strains bacterial in question and best stability physicochemical;being chosen among the evaluators of the organoleptic properties liquidsoap prepared with essential oil of cinnamon as the favorite on the nail, by presentingbetter aroma and appearance. Concluding that the antiseptic liquid soaps from 2% ofessential oil of Eugenia caryophyllata T. and Cinnamomum verum J. presented promisingresults; also, all the indicators physicochemical and chemical evaluated werekept, which gives us an indication of the correct formulation from the pharmaceuticalpoint of view

Parásitos de alevinos de gamitana (Colossoma macropomum) y paco (Piaractus brachypomus) cultivados en el C.I. Quistococha, Loreto, Perú

En acuicultura, los peces son susceptibles al ataque de virus, bacterias, hongos y ectoparásitos. Estos organismos se tornan en un serio problema cuando los peces se encuentran con bajas defensas naturales, se crían en altas densidades y/o se altera drásticamente la calidad de agua. El objetivo del presente estudio fue identificar la fauna de parásitos presentes en alevinos de paco (Piaractus brachypomus) y gamitana (Colossoma macropomum) provenientes de estanques del Centro de Investigación Quistococha del IIAP. Un total de 30 ejemplares de cada especie fueron examinados a través de la preparación de frotis fresco de branquias, piel, aletas y tubo digestivo. Entre las dos especies estudiadas, gamitana demostró una mayor prevalencia de infestación, mayor intensidad de parásitos y mayor índice de infestación parasitaria. Los alevinos de paco mostraron una mayor resistencia a la propagación y al ataque de parásitos. Se identificaron monogeneos de las familias Dactylogyridae y Gyrodactylidae, solo en gamitana, mientras que el protozoo ciliado Trichodina se halló exclusivamente en paco. Los parásitos identificados no causaron ninguna mortalidad en los peces