Trapping with biased diffusion species

We analyze a trapping reaction with a single penetrable trap, in a one dimensional lattice, where both species (particles and trap) are mobile and have a drift velocity. We obtain the density as seen from a reference system attached to the trap and from the laboratory frame. In addition we study the nearest neighbor distance to the trap. We exploit a stochastic model previously developed, and compare the results with numerical simulations, resulting in an excellent agreement.Comment: 6 pages, 7 Postscript figure

Na/K pump regulation of cardiac repolarization: Insights from a systems biology approach

The sodium-potassium pump is widely recognized as the principal mechanism for active ion transport across the cellular membrane of cardiac tissue, being responsible for the creation and maintenance of the transarcolemmal sodium and potassium gradients, crucial for cardiac cell electrophysiology. Importantly, sodium-potassium pump activity is impaired in a number of major diseased conditions, including ischemia and heart failure. However, its subtle ways of action on cardiac electrophysiology, both directly through its electrogenic nature and indirectly via the regulation of cell homeostasis, make it hard to predict the electrophysiological consequences of reduced sodium-potassium pump activity in cardiac repolarization. In this review, we discuss how recent studies adopting the Systems Biology approach, through the integration of experimental and modeling methodologies, have identified the sodium-potassium pump as one of the most\ud important ionic mechanisms in regulating key properties of cardiac repolarization and its rate-dependence, from subcellular to whole organ levels. These include the role of the pump in the biphasic modulation of cellular repolarization and refractoriness, the rate control of intracellular sodium and calcium dynamics and therefore of the adaptation of repolarization to changes in heart rate, as well as its importance in regulating pro-arrhythmic substrates through modulation of dispersion of repolarization and restitution. Theoretical findings are consistent across a variety of cell types and species including human, and widely in agreement with experimental findings. The novel insights and hypotheses on the role of the pump in cardiac electrophysiology obtained through this integrative approach could eventually lead to novel therapeutic and diagnostic strategies

Nucleic acids enrichment of fungal pathogens to study host-pathogen interactions

Fungal infections, ranging from superficial to life-threatening infections, represent a major public health problem that affects 25% of the worldwide population. In this context, the study of host-pathogen interactions within the host is crucial to advance antifungal therapy. However, since fungal cells are usually outnumbered by host cells, the fungal transcriptome frequently remains uncovered. We compared three different methods to selectively lyse human cells from in vitro mixes, composed of Candida cells and peripheral blood mononuclear cells. In order to prevent transcriptional modification, the mixes were stored in RNAlater. We evaluated the enrichment of fungal cells through cell counting using microscopy and aimed to further enrich fungal nucleic acids by centrifugation and by reducing contaminant nucleic acids from the host. We verified the enrichment of fungal DNA and RNA through qPCR and RT-qPCR respectively and confirmed that the resulting RNA has high integrity scores, suitable for downstream applications. The enrichment method provided here, i.e., lysis with Buffer RLT followed by centrifugation, may contribute to increase the proportion of nucleic acids from fungi in clinical samples, thus promoting more comprehensive analysis of fungal transcriptional profiles. Although we focused on C. albicans, the enrichment may be applicable to other fungal pathogens

Effect of Non Gaussian Noises on the Stochastic Resonance-Like Phenomenon in Gated Traps

We exploit a simple one-dimensional trapping model introduced before, prompted by the problem of ion current across a biological membrane. The voltage-sensitive channels are open or closed depending on the value taken by an external potential that has two contributions: a deterministic periodic and a stochastic one. Here we assume that the noise source is colored and non Gaussian, with a $q$-dependent probability distribution (where $q$ is a parameter indicating the departure from Gaussianity). We analyze the behavior of the oscillation amplitude as a function of both $q$ and the noise correlation time. The main result is that in addition to the resonant-like maximum as a function of the noise intensity, there is a new resonant maximum as a function of the parameter $q$.Comment: Communication to LAWNP01, Proceedings to be published in Physica D, RevTex, 8 pgs, 5 figure

Trapping Dynamics with Gated Traps: Stochastic Resonance-Like Phenomenon

We present a simple one-dimensional trapping model prompted by the problem of ion current across biological membranes. The trap is modeled mimicking the ionic channel membrane behaviour. Such voltage-sensitive channels are open or closed depending on the value taken by a potential. Here we have assumed that the external potential has two contributions: a determinist periodic and a stochastic one. Our model shows a resonant-like maximum when we plot the amplitude of the oscillations in the absorption current vs. noise intensity. The model was solved both numerically and using an analytic approximation and was found to be in good accord with numerical simulations.Comment: RevTex, 5 pgs, 3 figure

Comparison of the efficiency of different cell lysis methods and different commercial methods for RNA extraction from Candida albicans stored in RNAlater

Background: Obtaining sufficient RNA yield and quality for comprehensive transcriptomic studies is cumbersome for clinical samples in which RNA from the pathogen is present in low numbers relative to the nucleic acids from the host, especially for pathogens, such as yeasts, with a solid cell wall. Therefore, yeast cell lysis including cell wall disruption constitutes an essential first step to maximize RNA yield. Moreover, during the last years, different methods for RNA extraction from yeasts have been developed, ranging from classic hot phenol methods to commercially available specific kits. They offer different RNA yield and quality, also depending on the original storage medium, such as RNAlater. Results: We observed that, for C. albicans cells stored in Tryptic Soy Broth with 15% glycerol, 10min of bead beating in a horizontal position in RiboPure Lysis Buffer provided complete cell lysis. Cell lysis efficiency was decreased to 73.5% when cells were stored in RNAlater. In addition, the RiboPure Yeast Kit (Ambion) offered the highest RNA yield in comparison with the automated platform NucliSENS easyMAG total nucleic extraction (bioMerieux) and the RNeasy Mini Kit (Qiagen) according to NanoDrop and Fragment Analyzer. Moreover, we showed that, in spite of the decrease of cell lysis efficiency after RNAlater storage, as compared to storage in TSB+15% glycerol, RNAlater increased RNA yield during RNA extraction with both RiboPure Yeast Kit and easyMAG, as confirmed by Fragment Analyzer analysis and by RT-qPCR of the RNA from the Internal Transcribed Spacer 2. Conclusions: In our hands, the most efficient cell lysis and highest RNA yield from C. albicans cells stored in RNAlater was obtained by horizontal bead beating in RiboPure Lysis Buffer followed by RNA extraction with the RiboPure Yeast Kit

Juventud y paradojas de la modernidad: de los estilos de vida saludables al sedentarismo activo

El presente trabajo recoge los resultados de una investigación sobre las tendencias culturales en el abandono de la actividad física y el deporte entre la juventud española

EL FARO PORTUARIO DE MÁLAGA Y EL DESARROLLO COMERCIAL E INDUSTRIAL DE LA CIUDAD: ICONO URBANO Y ELEMENTO PAISAJÍSTICO

Desde su más remoto pasado histórico la ciudad de Málaga desarrolló una intensa actividad comercial a través de su puerto, que se intensificó en la segunda mitad del siglo XVIII con la exportación de vinos, aceites y cítricos y la liberación del comercio con América. Punto esencial en el desarrollo socio económico de la ciudad fueron sus instalaciones portuarias, mejoradas y ampliadas varias veces y que contaban con un faro de aceite móvil para garantizar la seguridad del tráfico marítimo. Acorde con el incremento del flujo naval se proyectó la construcción de un faro portuario estable por parte del ingeniero director de las obras del puerto, Joaquín Mª. de Pery, cuya construcción fue concluida en 1817. Posteriormente fue ampliada su base, mientras que el aparato óptico fue renovado varias veces hasta llegar al actual, eléctrico y automatizado. El emplazamiento en el muelle de Levante ha permitido que La Farola –como popularmente se la conoce-, haya gozado de una privilegiada visibilidad desde numerosos puntos de la ciudad, formando parte de su paisaje urbano y estableciendo una estrecha relación con la identidad colectiva de la población. Su presencia puede rastrearse en la pintura de paisaje y marinas de la ciudad, la carteleria de fiestas de invierno, carnaval y feria, la publicidad, logotipos comerciales y la publicidad, confirmando que sus valores patrimoniales sobrepasan su propia materialidad. Punto esencial de su interés es el hecho de que se mantiene actualmente en uso, emitiendo señales luminosas con arreglo a un código único y exclusivo del puerto de Málaga. Este cúmulo de circunstancias aconsejan adoptar la precauciones necesarias que garanticen su permanencia y uso, buen estado de conservación y que su presencia se tenga en cuenta en el planeamiento y la actividad constructiva de la zona para garantizar la permanencia de sus valores patrimoniales.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Informal Learning with a Gender Perspective Transmitted by Influencers through Content on YouTube and Instagram in Spain

[Abstract] The struggle for gender equality is based on identifying, understanding, and eradicating the causes of inequality. Digital media are and have always been governed by men and, as a consequence, have become another instrument of patriarchy. This article analyses the content created on YouTube and Instagram by four of the most popular influencers in Spain in order to examine the presence of stereotypes and gender roles, the use of sexist or inclusive language, and the influencers’ level of social engagement on issues related to gender equality. A content analysis approach using ATLAS.ti 8 software was chosen, as this method provides information about the sender of the message as the well the message itself and its impact. The findings of the analysis show that influencers transmit sexist roles and stereotypes, use non-inclusive language, and exhibit no social engagement on questions of gender inequality. The study concludes by highlighting the importance of cyberfeminism as a way of promoting gender equality online

Detection of Small-Scale Granular Structures in the Quiet Sun with the New Solar Telescope

Results of a statistical analysis of solar granulation are presented. A data set of 36 images of a quiet Sun area on the solar disk center was used. The data were obtained with the 1.6 m clear aperture New Solar Telescope (NST) at Big Bear Solar Observatory (BBSO) and with a broad-band filter centered at the TiO (705.7 nm) spectral line. The very high spatial resolution of the data (diffraction limit of 77 km and pixel scale of 0.$"$0375) augmented by the very high image contrast (15.5$\pm$0.6%) allowed us to detect for the first time a distinct subpopulation of mini-granular structures. These structures are dominant on spatial scales below 600 km. Their size is distributed as a power law with an index of -1.8 (which is close to the Kolmogorov's -5/3 law) and no predominant scale. The regular granules display a Gaussian (normal) size distribution with a mean diameter of 1050 km. Mini-granular structures contribute significantly to the total granular area. They are predominantly confined to the wide dark lanes between regular granules and often form chains and clusters, but different from magnetic bright points. A multi-fractality test reveals that the structures smaller than 600 km represent a multi-fractal, whereas on larger scales the granulation pattern shows no multi-fractality and can be considered as a Gaussian random field. The origin, properties and role of the newly discovered population of mini-granular structures in the solar magneto-convection are yet to be explored.Comment: 13 pages, 5 figure