659 research outputs found

    Notas cariosistemáticas sobre flora española, I

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    Se ha estudiado el número cromosómico de 21 táxones ibéricos. Creemos nuevos para la ciencia los recuentos siguientes: Gypsophila struthium Loefl. (2n=34); Lepidium subulatum L. (2n=16); Iberis cinerea Poiret (2n=44); Erucastrum nasturtiifolium (Poiret) O. E. Schulz var. subbipinnatifidum (Lag.) Thell. (2n=16); Teucrium gnaphalodes L'Hér. subsp. jaënnense (Lacaita) Rivas-Martínez (2n=26); Teucrium pumilum L. (2n=26); Centaurea alpina L. (2n=30); Centaurea hyssopifolia Vahl (2n=22); Launaea resedifolia (L.) O. Kuntzee (2n=18).Se reivindica el rango específico para Iberis cinerea Poiret y se insiste sobre la identidad de Centaurea linaresii Láz. Ibiza y C. alpina L.The cromosome numbers of 21 Iberian taxa have been studied. The following numbers are, to our knowledge, new to science: Gypsophila struthium Loefl. (2n=34); Lepidium subulatum L. (2n=16); Iberis cinerea Poiret (2n=44); Erucastrum nasturtiifolium (Poiret) O. E. Schluz var. subbipinnatifidum (Lag.) Thell. (2n=16); Teucrium gnaphalodes L'Hér. subsp. jaënnense (Lacaita) Rivas-Martínez (2n=26); Teucrium pumilum L. (2n=26); Centaurea alpina L. (2n=30); Centaurea hyssopifolia Vahl (2n=22); Launaea resedifolia (L.) O. Kuntzee (2n=18).Specific rank is restored for Iberis cinerea Poiret, and the identity of Centaurea linaresii Láz. Ibiza and C. alpina L. is remarked

    Fractional and scaled Brownian motion on the sphere: The effects of long-time correlations on navigation strategies

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    We analyze long-time correlated Brownian motion and scaled Brownian motion on the surface of the two dimensional sphere S2\mathbb{S}^{2}. Due to the geometric effects induced by the S2\mathbb{S}^{2} curvature, such correlations collude with specific dynamics (\emph{navigation strategies}) on the manifold topology to originate rich transport properties. We focus our study to two classes of navigation strategies: One induced by the specific set of coordinates chosen for S2\mathbb{S}^2 which defines a fixed frame of reference; in particular, we chose the basis induced by spherical coordinates. We find that contrary to what occurs in the absence of correlations non-equilibrium stationary distributions are attained. We elucidate an analogy of our results with those observed of fractional Brownian motion in confined by reflecting walls in one and two dimensions. In contrast, when the navigation strategy chosen corresponds to a frame of reference moving with the particle as does the Frenet-Serret system, then the equilibrium uniform distribution on the sphere is attained. In both cases, the relaxation times towards the stationary distribution depend on the particular value of the Hurst parameter. We show that scaled Brownian motion on S2\mathbb{S}^2 is independent of the navigation strategy and we find a good agreement between the analytical calculations obtained from the solution of a time-dependent diffusion equation on S2\mathbb{S}^{2} and the numerical results obtained from our method to generate ensemble of trajectories.Comment: The statistics of Fractional Brownian motion and of scaled Brownian motion are analyzed when motion is constrained to surface of a spher

    Anomalous diffusion of scaled Brownian tracers

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    A model for anomalous transport of tracer particles diffusing in complex media in two dimensions is proposed. The model takes into account the characteristics of persistent motion that active bath transfer to the tracer, thus the model proposed in here extends active Brownian motion, for which the stochastic dynamics of the orientation of the propelling force is described by scale Brownian motion (sBm), identified by a the time dependent diffusivity of the form Dβtβ1D_\beta\propto t^{\beta-1}, β>0\beta>0. If β1\beta\neq1, sBm is highly non-stationary and suitable to describe such a non-equilibrium dynamics induced by complex media. In this paper we provide analytical calculations and computer simulations to show that genuine anomalous diffusion emerge in the long-time regime, with a time scaling of the mean square displacement t2βt^{2-\beta}, while ballistic transport t2t^2, characteristic of persistent motion, is found in the short-time one. An analysis of the time dependence of the kurtosis, and intermediate scattering function of the positions distribution, as well as the propulsion auto-correlation function, which defines the effective persistence time, are provided.Comment: 8 pages, 5 figure

    Desarrollo de un servicio experimental de teledetección en los riegos del Porma (León) para el cálculo ajustado de necesidades hídricas y mejora en la gestión del regadío

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    El proyecto de innovación tecnológica OPTIREG Eficiencia Hídrica, impulsado por el Grupo Tragsa, tiene entre sus objetivos principales introducir el uso de la teledetección, como tecnología de apoyo a la gestión hídrica. Para ello se está desarrollando un servicio web gis experimental que servirá de repositorio único de imágenes y de sus productos derivados y que facilitará, tanto a los regantes, como a los gestores del riego, el seguimiento de los cultivos y de sus necesidades hídricas. Diversos estudios científicos han demostrado la buena relación lineal existente entre el índice de vegetación normalizado (NDVI), derivado de las imágenes de satélite, y el coeficiente de cultivo, Kc (Torres, 2010), utilizado en el cálculo de la evapotranspiración y las necesidades hídricas. Una primera evaluación de los resultados obtenidos en la campaña 2015 para los principales cultivos en regadío en la zona de estudio del Porma (León), indica que el Kc calculado a partir del NDVI, se ajusta mejor que el de FAO. Por ello, se considera un sistema muy válido como referencia para ajustar no sólo la cantidad de agua, sino también para determinar el momento más adecuado de riego, que redundará en una mayor eficiencia hídrica

    Clinical relevance of the transcriptional signature regulated by CDC42 in colorectal cancer

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    CDC42 is an oncogenic Rho GTPase overexpressed in colorectal cancer (CRC). Although CDC42 has been shown to regulate gene transcription, the specific molecular mechanisms regulating the oncogenic ability of CDC42 remain unknown. Here, we have characterized the transcriptional networks governed by CDC42 in the CRC SW620 cell line using gene expression analysis. Our results establish that several cancer-related signaling pathways, including cell migration and cell proliferation, are regulated by CDC42. This transcriptional signature was validated in two large cohorts of CRC patients and its clinical relevance was also studied. We demonstrate that three CDC42-regulated genes offered a better prognostic value when combined with CDC42 compared to CDC42 alone. In particular, the concordant overexpression of CDC42 and silencing of the putative tumor suppressor gene CACNA2D2 dramatically improved the prognostic value. The CACNA2D2/CDC42 prognostic classifier was further validated in a third CRC cohort as well as in vitro and in vivo CRC models. Altogether, we show that CDC42 has an active oncogenic role in CRC via the transcriptional regulation of multiple cancer-related pathways and that CDC42-mediated silencing of CACNA2D2 is clinically relevant. Our results further support the use of CDC42 specific inhibitors for the treatment of the most aggressive types of CRCThis work has been supported by grants to JCL from Ministerio de Ciencia e Innovación (SAF2008- 03750, RD06-0020-0016 and RD12/0036/0019) and to DGO Cancer Institute New South Wales (2017/CDF625). FVM is a National Breast Cancer Foundation/Cure Cancer Australia Foundation Postdoctoral Training Fellow

    The CD14 (−159 C/T) SNP is associated with sCD14 levels and allergic asthma, but not with CD14 expression on monocytes

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    LPS-ligation to CD14/TLR-4 on monocytes/macrophages triggers the production of IL-12-family cytokines. IL12/18 promote TH1-differentiation, counteracting the TH2-driven asthma. Therefore, CD14 modulation could alter the TH2-differentiation and should be taken into account when studying asthma. To analyse the alteration in CD14 levels and its association with CD14 (−159 C/T) SNP (rs2569190) in Caucasian adults with stable allergic asthma, we performed a cross-sectional study (277 healthy subjects vs. 277 patients) where clinical parameters, CD14 values and the CD14 (−159 C/T) SNP were studied. Apart from typical biomarkers, we found an increment of neuron-specific enolase (NSE) in allergic asthma, probably linked to monocyte activity. Indeed, we evidenced increased monocyte numbers, but lower CD14 expression and normalised sCD14 values in patients. Moreover, we noticed an association of the T allele (P = 0.0162) and TT genotype (P = 0.0196) of the CD14 SNP with a decreased risk of allergic asthma and augmented sCD14 levels. In conclusion, monocyte CD14 expression and normalized sCD14 values were reduced in stable state asthmatics, and this could be related to the presence of an expanded CD14low monocyte subset. This study also demonstrates that the CD14 (−159 C/T) polymorphism is a risk factor for moderate-severe allergic asthma in adult CaucasiansThis study was funded by grants from Sociedad Española de Neumología y Cirugía Torácica, (SEPAR) (121/2012) and Instituto de Salud Carlos III, Ministerio de Economía y Competitividad (Fondo de Investigación Sanitaria, FIS; co-financed by European Union ERDF funds) (PI13/02046). JJNF is a recipient of a Xunta de Galicia Fellowship (Co-financed by European Social Fund (ESF))S

    High efficiency wireless video networks for next generation of ENG services

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    This work has been partially funded by the CDTI under the FREEDOM (Servicios de Videocomunicaciones de Alta Eficiencia para Redes Inalámbricas de Nueva Generación en Movilidad) project, with Reference Number IDI20120486.Ruiz, D.; Giménez Gandia, JJ.; Gómez Barquero, D.; Anaya, JJ.; Fernández, FJ.; Valdés Francisco J.; Barjau, C.... (2013). High efficiency wireless video networks for next generation of ENG services. Waves. 5-16. http://hdl.handle.net/10251/55008S51
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