Complex noise in diffusion-limited reactions of replicating and competing species

We derive exact Langevin-type equations governing quasispecies dynamics. The inherent multiplicative noise has both real and imaginary parts. The numerical simulation of the underlying complex stochastic partial differential equations is carried out employing the Cholesky decomposition for the noise covariance matrix. This noise produces unavoidable spatio-temporal density fluctuations about the mean field value. In two dimensions, the fluctuations are suppressed only when the diffusion time scale is much smaller than the amplification time scale for the master species.Comment: 10 pages, 2 composite figure

Statistical Complexity and Nontrivial Collective Behavior in Electroencephalografic Signals

We calculate a measure of statistical complexity from the global dynamics of electroencephalographic (EEG) signals from healthy subjects and epileptic patients, and are able to stablish a criterion to characterize the collective behavior in both groups of individuals. It is found that the collective dynamics of EEG signals possess relative higher values of complexity for healthy subjects in comparison to that for epileptic patients. To interpret these results, we propose a model of a network of coupled chaotic maps where we calculate the complexity as a function of a parameter and relate this measure with the emergence of nontrivial collective behavior in the system. Our results show that the presence of nontrivial collective behavior is associated to high values of complexity; thus suggesting that similar dynamical collective process may take place in the human brain. Our findings also suggest that epilepsy is a degenerative illness related to the loss of complexity in the brain.Comment: 13 pages, 3 figure

La creación de discurso ideológico en el cine popular del tardofranquismo (1966-1975): el ‘ciclo Paco Martínez Soria’

El cine popular de los últimos años del franquismo gozó de un importante éxito comercial gracias a películas que, bajo la apariencia de un entretenimiento sencillo, reflejaban y/o generaban una visión concreta sobre un momento histórico de cambio. La producción del período tardofranquista encontró un filón en algunos grupos de obras, entre los que destaca la decena de largometrajes protagonizados por el actor Paco Martínez Soria. Su filmografía admite una lectura en clave ideológica que se concreta en una defensa de la tradición frente a la novedad gracias a una figura patriarcal y benefactora que asegura la estabilidad de las comunidades a las que pertenece

Monte Carlo simulations of post-common-envelope white dwarf + main sequence binaries: comparison with the SDSS DR7 observed sample

Detached white dwarf + main sequence (WD+MS) systems represent the simplest population of post-common envelope binaries (PCEBs). Since the ensemble properties of this population carries important information about the characteristics of the common-envelope (CE) phase, it deserves close scrutiny. However, most population synthesis studies do not fully take into account the effects of the observational selection biases of the samples used to compare with the theoretical simulations. Here we present the results of a set of detailed Monte Carlo simulations of the population of WD+MS binaries in the Sloan Digital Sky Survey (SDSS) Data Release 7. We used up-to-date stellar evolutionary models, a complete treatment of the Roche lobe overflow episode, and a full implementation of the orbital evolution of the binary systems. Moreover, in our treatment we took into account the selection criteria and all the known observational biases. Our population synthesis study allowed us to make a meaningful comparison with the available observational data. In particular, we examined the CE efficiency, the possible contribution of internal energy, and the initial mass ratio distribution (IMRD) of the binary systems. We found that our simulations correctly reproduce the properties of the observed distribution of WD+MS PCEBs. In particular, we found that once the observational biases are carefully taken into account, the distribution of orbital periods and of masses of the WD and MS stars can be correctly reproduced for several choices of the free parameters and different IMRDs, although models in which a moderate fraction (<=10%) of the internal energy is used to eject the CE and in which a low value of CE efficiency is used (<=0.3) seem to fit better the observational data. We also found that systems with He-core WDs are over-represented in the observed sample, due to selection effects.Comment: 15 pages, 7 figures, accepted for publication in A&

What do we know about sex education of people with intellectual disabilities? An umbrella review

Abstract. Special attention is required when considering any educational intervention aimed at its promotion and development. Our objective is to conduct an umbrella review of systematic reviews that gather evidence from relationships and sex education programmes tailored for individuals with intellectual disabilities.MethodsThe protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐analyses Protocol. Systematic reviews were identified through a search in Web of Science, SCOPUS and PsychINFO, using the descriptors: ‘intellectual disab*’ AND ‘sex*’AND ‘systematic’.FindingsThe results of the nine reviews included in the meta‐review yield relevant outcomes related to 50 sex education interventions carried out with people with intellectual disabilities. This provided the opportunity to delve into the characteristics of these interventions to ascertain the accomplishments achieved to date.ConclusionsThe findings serve as foundation to propose and promote new research on this important area of life, addressing the inequalities identified concerning the sexuality and affective‐sexual education of people with intellectual disabilities. It offers valuable information for the educational, social and healthcare fields, facilitating the design of more effective and rights‐respecting initiatives

Secreción de dominios extracelulares de proteínas asociadas a cáncer, en E. Coli BL21 y en células HEK293FT.

En Panamá, el cáncer es la segunda causa más frecuente de defunciones. Entre los cánceres más comunes se encuentran el cáncer de pulmón, uterino, de mama, de colon y próstata. Cáncer no quiere decir muerte, entre más temprano se puede detectar más fácil será eliminado. En la actualidad, existen distintos tratamientos innovadores basados en anticuerpos, que están revolucionando el campo, como los son los de "checkpoint inhi bitor" utilizados en inmunoterapia oncológica, como otros expresados en las células de cáncer (EGFR, CD22, etc.). En este proyecto, se estableció una plataforma de expresión de proteínas en células humanas y en bacterias, E.coli BL21 (DE3) pLysS. Se han seleccionado varias proteínas que están expresadas en cánceres, como también en el sistema inmune. Estas serán utilizadas para estudiar su función en células de cáncer, como también para elaborar nanocuerpos específicos. Se amplificaron las secuencias de genes de las proteínas extracelulares y fueron donadas en bacterias, y finalmente, se produjo cada dominio extracelular de los receptores (AXL, CD32, CLEC5A y CLEC7A) en bacterias E. col¡ BL21 (DE3) pLysS y en células HEK293FT

Size-dependent photoacclimation of the phytoplankton community in temperate shelf waters (southern Bay of Biscay)

Shelf waters of the Cantabrian Sea (southern Bay of Biscay) are productive ecosystems with a marked seasonality. We present the results from 1 yr of monthly monitoring of the phytoplankton community together with an intensive sampling carried out in 2 contrasting scenarios during the summer and autumn in a mid-shelf area. Stratification was apparent on the shelf in summer, while the water column was comparatively well mixed in autumn. The size structure of the photoautotrophic community, from pico-to micro-phytoplankton, was tightly coupled with the meteo-climatic and hydrographical conditions. Over the short term, variations in the size structure and chlorophyll content of phytoplankton cells were related to changes in the physico-chemical environment, through changes in the availability of nutrients and light. Uncoupling between the dynamics of carbon biomass and chlorophyll resulted in chlorophyll to carbon ratios dependent on body size. The slope of the size dependence of chlorophyll content increased with increasing irradiance, reflecting different photoacclimation plasticity from pico-to micro-phytoplankton. The results have important implications for the productivity and the fate of biogenic carbon in this region, since the size dependence of photosynthetic rates is directly related to the size scaling of chlorophyll content.Versión del edito

Photoacclimation of picophytoplankton in the central Cantabrian Sea

Photoacclimation of picophytoplankton was studied in the mixed layer of 3 stations in the central Cantabrian Sea (southern Bay of Biscay). Picophytoplankton chl a:carbon ratios (θ) presented minimum values during summer, when irradiance, temperature, and biomass of prokaryotes reached maximum values and inorganic nutrient concentrations were low. Conversely, the maximum θ were reached during winter, coincident with lowest annual irradiance but maximum concentration of inorganic nutrients and higher relative biomass of eukaryotes. Changes in θ were modeled using irradiance as an independent variable. Exponentially decreasing functions of θ with irradiance were significant only when the mean temperatures in the mixed layer were above 14°C. These functions presented light-saturated minimum ratios (θmin) that decreased linearly with temperature and low-light maximum ratios (θmax) that increased exponentially with temperature. Such relationships were used to establish an empirical model that reproduced the seasonality of picophytoplankton θ in the mixed layer, with minima in summer and maxima in winter. A maximum potential θ, θN,T-max, was determined to estimate picophytoplankton growth rates in the central Cantabrian Sea. Combinations of picophytoplankton growth rates and biomass in the mixed layer were used to estimate areal picophytoplankton primary production rates in the euphotic zone that presented a bimodal seasonal cycle, with maxima in late winter (ca. 100 mg C m-2 d-1) and in late autumn (>200 mg C m-2 d-1) and mean annual values around 120 mg C m-2 d-1.En prens