41 research outputs found

    Emergent global oscillations in heterogeneous excitable media: The example of pancreatic beta cells

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    Using the standard van der Pol-FitzHugh-Nagumo excitable medium model I demonstrate a novel generic mechanism, diversity, that provokes the emergence of global oscillations from individually quiescent elements in heterogeneous excitable media. This mechanism may be operating in the mammalian pancreas, where excitable beta cells, quiescent when isolated, are found to oscillate when coupled despite the absence of a pacemaker region.Comment: See home page http://lec.ugr.es/~julya

    Cytogenetic and genomic analysis of a patient with turner syndrome and t(2;12): a case report

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    Background: Turner syndrome is a genetic disorder that afects women. It is caused by an absent or incomplete X chromosome, which can be presented in mosaicism or not. There are 12 cases of Turner syndrome patients who present structural alterations in autosomal chromosomes. Case presentation: The present case report describes a patient with a reciprocal, maternally inherited translocation between chromosomes 2 and 12 with a mosaicism of X monosomy 45,X,t(2;12)(p13;q24)[95]/46,XX,t(2;12)(p13;q24) [5]. Through genetic mapping arrays, altered genes in the patient were determined within the 23 chromosome pairs. These genes were associated with the patient’s clinical features using a bioinformatics tool Conclusion: To our knowledge, this is the frst case in which a translocation (2;12) is reported in a patient with Turner syndrome and confrmed by conventional cytogenetics, FISH and molecular genetics. Clinical features of our patient are closely related with the loss of one X chromosome, however mild intellectual disability can be likely explained by autosomal genes. The presence of familial translocations was a common fnding, thus emphasizing the need for familiar testing for further genetic counselling

    A Quick Guide for Using Microsoft Onenote as an Electronic Laboratory Notebook

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    [Abstract] Scientific data recording and reporting systems are of a great interest for endorsing reproducibility and transparency practices among the scientific community. Current research generates large datasets that can no longer be documented using paper lab notebooks (PLNs). In this regard, electronic laboratory notebooks (ELNs) could be a promising solution to replace PLNs and promote scientific reproducibility and transparency. We previously analyzed five ELNs and performed two survey-based studies to implement an ELN in a biomedical research institute. Among the ELNs tested, we found that Microsoft OneNote presents numerous features related to ELN best functionalities. In addition, both surveyed groups preferred OneNote over a scientifically designed ELN (PerkinElmer Elements). However, OneNote remains a general note-taking application and has not been designed for scientific purposes. We therefore provide a quick guide to adapt OneNote to an ELN workflow that can also be adjusted to other nonscientific ELNs

    USO DE MICROSOFT ONENOTE COMO CUADERNO ELECTRÓNICO DE LABORATORIO

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    Los sistemas de registro y de reporte de datos son de gran interés, puesto que respaldan la reproducibilidad y transparencia científica. La investigación actual genera una gran cantidad de datos que ya no se pueden documentar utilizando cuadernos de laboratorio de papel (CLP). Los cuadernos electrónicos de laboratorio (CEL) podrían ser una solu-ción prometedora para reemplazar los CLP y promover la reproducibilidad científica y su transparencia. Anteriormente analizamos cinco CEL y realizamos dos encuestas para implementar un CEL en un instituto de investigación biomédica. Entre los CEL proba-dos, encontramos que Microsoft OneNote presenta numerosas características relacio-nadas con las mejores funcionalidades del CEL. Además, ambos grupos encuestados prefirieron OneNote sobre un CEL científico (Elements de PerkinElmer). Sin embargo, OneNote es una aplicación general para tomar notas que no ha sido diseñada para fi-nes científicos. Por lo tanto, en este trabajo proporcionamos varias pautas para adaptar OneNote a un flujo de trabajo experimental

    Planck 2013 results. XXII. Constraints on inflation

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    We analyse the implications of the Planck data for cosmic inflation. The Planck nominal mission temperature anisotropy measurements, combined with the WMAP large-angle polarization, constrain the scalar spectral index to be ns = 0:9603 _ 0:0073, ruling out exact scale invariance at over 5_: Planck establishes an upper bound on the tensor-to-scalar ratio of r < 0:11 (95% CL). The Planck data thus shrink the space of allowed standard inflationary models, preferring potentials with V00 < 0. Exponential potential models, the simplest hybrid inflationary models, and monomial potential models of degree n _ 2 do not provide a good fit to the data. Planck does not find statistically significant running of the scalar spectral index, obtaining dns=dln k = 0:0134 _ 0:0090. We verify these conclusions through a numerical analysis, which makes no slowroll approximation, and carry out a Bayesian parameter estimation and model-selection analysis for a number of inflationary models including monomial, natural, and hilltop potentials. For each model, we present the Planck constraints on the parameters of the potential and explore several possibilities for the post-inflationary entropy generation epoch, thus obtaining nontrivial data-driven constraints. We also present a direct reconstruction of the observable range of the inflaton potential. Unless a quartic term is allowed in the potential, we find results consistent with second-order slow-roll predictions. We also investigate whether the primordial power spectrum contains any features. We find that models with a parameterized oscillatory feature improve the fit by __2 e_ _ 10; however, Bayesian evidence does not prefer these models. We constrain several single-field inflation models with generalized Lagrangians by combining power spectrum data with Planck bounds on fNL. Planck constrains with unprecedented accuracy the amplitude and possible correlation (with the adiabatic mode) of non-decaying isocurvature fluctuations. The fractional primordial contributions of cold dark matter (CDM) isocurvature modes of the types expected in the curvaton and axion scenarios have upper bounds of 0.25% and 3.9% (95% CL), respectively. In models with arbitrarily correlated CDM or neutrino isocurvature modes, an anticorrelated isocurvature component can improve the _2 e_ by approximately 4 as a result of slightly lowering the theoretical prediction for the ` <_ 40 multipoles relative to the higher multipoles. Nonetheless, the data are consistent with adiabatic initial conditions

    Planck 2015 results. XX. Constraints on inflation

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    We present the implications for cosmic inflation of the Planck measurements of the cosmic microwave background (CMB) anisotropies in both temperature and polarization based on the full Planck survey. The Planck full mission temperature data and a first release of polarization data on large angular scales measure the spectral index of curvature perturbations to be n s = 0.968 ± 0.006 and tightly constrain its scale dependence to dn s /dlnk = −0.003 ± 0.007 when combined with the Planck lensing likelihood. When the high-ℓ polarization data is included, the results are consistent and uncertainties are reduced. The upper bound on the tensor-to-scalar ratio is r 0.002 <0.11 (95% CL), consistent with the B-mode polarization constraint r<0.12 (95% CL) obtained from a joint BICEP2/Keck Array and Planck analysis. These results imply that V(ϕ)∝ϕ 2 and natural inflation are now disfavoured compared to models predicting a smaller tensor-to-scalar ratio, such as R 2 inflation. Three independent methods reconstructing the primordial power spectrum are investigated. The Planck data are consistent with adiabatic primordial perturbations. We investigate inflationary models producing an anisotropic modulation of the primordial curvature power spectrum as well as generalized models of inflation not governed by a scalar field with a canonical kinetic term. The 2015 results are consistent with the 2013 analysis based on the nominal mission data

    Intervenciones aleatorias controladas basadas en las escuelas para prevenir la obesidad infantil: revisión sistemática de 2006 a 2009 Randomized controlled school based interventions to prevent childhood obesity: systematic review from 2006 to 2009

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    La prevalencia de sobrepeso y obesidad en niños ha incrementado a niveles epidémicos. Diferentes autores sugieren que la escuela puede ser el espacio más apropiado para realizar programas efectivos de prevención. El propósito de esta revisión sistemática fue valorar la evidencia de estudios aleatorios controlados con un periodo de intervención a largo plazo (igual o mayor a 9 meses) en escuelas y publicados en la base de datos de MEDLINE/PubMed del 1º de enero de 2006 hasta el 28 de febrero de 2009. Se analizaron en total 10 artículos. En general, se puede observar una heterogeneidad en el diseño y los componentes de la intervención, la edad del grupo objetivo, el tiempo de intervención, el sistema educativo, las características culturales de la población y los resultados. Estos últimos son modestos. Los resultados indican un cambio positivo en el estilo de vida, incremento en el consumo de frutas y verduras, menor consumo de bebidas carbonatadas y azucaradas, reducción del comportamiento sedentario y reducción en adiposidad. En general no hubo reducción significativa del IMC. Los resultados demandan estrategias para lograr mayor compromiso de los padres y adherencia a los programas, así como más estudios en diferentes sistemas educativos y ambientes culturales, incluyendo los de Latinoamérica. Además se requieren seguimientos a más largo plazo.The prevalence of overweight and obesity in children has increased to epidemic levels. Several authors have suggested that school is the best place for effective prevention programs. The purpose of this systematic review was to assess the evidence of randomized controlled trials concerning long-term (equal to or more than 9 months) observations at schools and published in the database of MEDLINE/Pubmed from January 1st of 2006 to February 28 of 2009. Ten studies were analyzed. Overall, regarding the design, the intervention components, target population age, intervention periods, educational techniques, cultural characteristics of the population, and outcome measures were heterogeneous. The results were modest. The outcomes showed a positive impact on lifestyle as intakes of fruits and vegetables increased, consumption of sugar-sweetened carbonated beverages decreased, and sedentary behaviors and adiposity were reduced. Generally, there were no significant reductions for BMI. These results warrant more strategies to achieve parental involvement, reduction of dropouts, and additional studies assessing different educational systems and cultural environments, including those in Latin America. Longer follow-up periods are also required

    Predictive model for the emergence of Xylotrechus arvicola (coleoptera Cerambycidae) in La Rioja vineyards (Spain)

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    Xylotrechus arvicola (Coleoptera, Cerambycidae) (Olivier) is a polyphagous borer which attacks different woody species in natural habitats in Spain. This coleopteran is also becoming a real impacting pest in several Spanish wine producing territories. Infested vines show adult exit holes, rachitic shoots, a higher incidence of wood fungal diseases and fragility. At the beginning of the 1990s, a heavy increase of infestation was observed in La Rioja vineyards, the only Qualified Guarantee of Origin Region (A.O.C.) in Spain. Due to the endophytic development of the larvae of X. arvicola, adults are the designated target for the integrated management. Therefore, the aim of the present paper was to study the flight period of the pest and to calculate the value of degree-days for the emergence of both sexes from data collected in the field during 2003-2008 in a Tempranillo cultivar in Tirgo (La Rioja). Adult emergences occurred from the end of May to mid-August and a certain degree of protandry was detected. The predictive models obtained for each year fit a sinusoidal curve in all cases, except for males in 2004, when the adjustment was polynomial. The obtained correlation coefficients were considerably high, as the value 0.99 was exceeded in 72% of the cases. These results obtained in La Rioja vineyards suggest that control strategies aimed at the reduction of the adult population of X. arvicola in the view of the integrated management, should be performed between mid-June and the end of July

    Intervenciones aleatorias controladas basadas en las escuelas para prevenir la obesidad infantil: revisión sistemática de 2006 a 2009

    No full text
    La prevalencia de sobrepeso y obesidad en niños ha incrementado a niveles epidémicos. Diferentes autores sugieren que la escuela puede ser el espacio más apropiado para realizar programas efectivos de prevención. El propósito de esta revisión sistemática fue valorar la evidencia de estudios aleatorios controlados con un periodo de intervención a largo plazo (igual o mayor a 9 meses) en escuelas y publicados en la base de datos de MEDLINE/PubMed del 1º de enero de 2006 hasta el 28 de febrero de 2009. Se analizaron en total 10 artículos. En general, se puede observar una heterogeneidad en el diseño y los componentes de la intervención, la edad del grupo objetivo, el tiempo de intervención, el sistema educativo, las características culturales de la población y los resultados. Estos últimos son modestos. Los resultados indican un cambio positivo en el estilo de vida, incremento en el consumo de frutas y verduras, menor consumo de bebidas carbonatadas y azucaradas, reducción del comportamiento sedentario y reducción en adiposidad. En general no hubo reducción significativa del IMC. Los resultados demandan estrategias para lograr mayor compromiso de los padres y adherencia a los programas, así como más estudios en diferentes sistemas educativos y ambientes culturales, incluyendo los de Latinoamérica. Además se requieren seguimientos a más largo plazo
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