Density estimates on a parabolic spde

We consider a general class of parabolic spde's [formula] with (t, x) [member of] [0, T]×[0, 1] and [epsilon]Wt,x, [epsilon] > 0, a perturbed Gaussian space-time white noise. For (t, x) [member of] (0, T]×(0, 1) we prove the called Davies and Varadhan-Léandre estimates of the density p[epsilon]t,x of the solution u[epsilon]t,x

A new battery-charging method suggested by molecular dynamics simulations

Based on large-scale molecular dynamics simulations, we propose a new charging method that should be capable of charging a Lithium-ion battery in a fraction of the time needed when using traditional methods. This charging method uses an additional applied oscillatory electric field. Our simulation results show that this charging method offers a great reduction in the average intercalation time for Li+ ions, which dominates the charging time. The oscillating field not only increases the diffusion rate of Li+ ions in the electrolyte but, more importantly, also enhances intercalation by lowering the corresponding overall energy barrier.Comment: 11 pages, 5 figure

Valor nutricional de los ácidos grasos de los peces de agua dulce neotropicales Prochilodus magdalenae, Pseudoplatystoma magdaleniatum y Ageneiosus pardalis

This study aimed to determine the nutritional value of the fatty acids in the freshwater fish Prochilodus magdalenae, Pseudoplatystoma magdaleniatum and Ageneiosus pardalis during dry and wet Neotropical seasons with the view to generate useful information for nutrition and sustainable commercial exploitation. The analysis of fatty acids was performed by gas chromatography–mass spectrometry and the nutritional value was calculated using five estimators: n-6/n-3 ratio, unsaturation index (UI), atherogenicity index (AI), thrombogenicity index (TI) and ratio of hypocholesterolemic/hypercholesterolemic (h/H) fatty acids. A different number of fatty acids (P. magdaleniatum = 50, P. magdalenae = 41, and A. pardalis = 32) was identified for each species and the average abundance percentages were different in the two seasons (p < 0.05). Prochilodus magdalenae and P. magdaleniatum showed healthy n-6/n-3 ratios (1.04 and 2.72) in the different seasons. Although the three species showed low values of UI (0.37–0.63), the remaining nutritional indexes were within the healthy range (AI: 0.04–0.70, TI: 0.66–1.07, h/H: 0.80 – 24.40). Multivariate analysis showed similar healthy nutritional values for the species, with exception of P. magdaleniatum.En este estudio se determinó el valor nutricional de ácidos grasos presentes en las especies P. magdaleniatum, P. magdalenae y A. pardalis en los periodos lluvioso y seco, con el fin de generar información útil para una nutrición saludable y una explotación comercial sostenible. El análisis de los ácidos grasos se realizó por CG-EM y el valor nutricional se estimó mediante relación n-6/n-3, índices de insaturación (II), aterogenicidad (IA), trombogenicidad (IT) y relación de ácidos grasos hipocolesterolémicos/hipercolesterolémicos (h/H). Se identificaron números diferentes de ácidos grasos en cada especie (P. magdaleniatum = 50, P. magdalenae = 41 and A. pardalis = 32) y las medias de los porcentajes mayoritarios fueron diferentes en los dos periodos (p < 0,05). Las especies P. magdalenae y P. magdaleniatum mostraron relaciones n-6/n-3 saludables (1,04 y 2,72) en periodos diferentes. Aunque las tres especies mostraron valores II bajos (0,37-0,63), los demás índices IA (0,04-0,70), TI (0,66-1,07) y h/H (0,80 – 24,40) están dentro del rango saludable. El análisis multivariante mostró valores nutricionales similares en dos especies excepto P. magdaleniatum

A novel topology of high-speed SRM for high-performance traction applications

A novel topology of high-speed Switched Reluctance Machine (SRM) for high-performance traction applications is presented in this article. The target application, a Hybrid Electric Vehicle (HEV) in the sport segment poses very demanding specifications on the power and torque density of the electric traction machine. After evaluating multiple alternatives, the topology proposed is a 2-phase axial flux machine featuring both segmented twin rotors and a segmented stator core. Electromagnetic, thermal and mechanical models of the proposed topology are developed and subsequently integrated in an overall optimisation algorithm in order to find the optimal geometry for the application. Special focus is laid on the thermal management of the machine, due to the tough thermal conditions resulting from the high frequency, high current and highly saturated operation. Some experimental results are also included in order to validate the modelling and simulation results

The teaching strategies in the Teaching-Learning proccess of reading skill in eleventh grade, section B at public high school "Augusto Calderon Sandino" in Niquinohomo during the period from March to Octuber 2014

Over the last twenty years, there has been growing interest in incorporating a significant focus on Reading skill into the language curricula. There is a general belief that such focus will help students become more successful learners and it facilitates the activation of the comprehension. It is also assumed that learners who have developed skills in Reading will be able to exploit classroom-learning opportunities effectively, and they will be more adequately equipped to continue with language learning outside the classroom. Reading is the most basic skill, it provides access to other skills and knowledge, facilitates life-long learning, and it opens doors to opportunities in life in several aspects.Thi

Implementación del servicio de mobile-learning para la universidad Antonio Nariño

El proceso de enseñanza aprendizaje en el entorno académico universitario en los últimos años ha presenciado notables cambios, empezando por la implementación de Internet en las aulas, en conjunto con diversas herramientas de la web 2.0, dando como resultado métodos de enseñanza tales como el Blended- Learning y posteriormente el E- Learning. Como complemento a lo anterior, aparece el aprendizaje electrónico móvil o M-learning, el cual ha venido tomando fuerza conforme la tecnología de dispositivos móviles crece tanto en la implementación de recursos computacionales, como en el ancho de banda para la gestión de los mismos, sumado a la masificación en su uso dentro de la comunidad académica. Este desarrollo ha conllevado, a que actualmente la gestión de información (voz, datos y video), se haga cada vez más a través de distintos tipos de dispositivo móvil, lo que ha permitido abrir toda una amplia gama de aplicaciones tanto en el ámbito académico como corporativo, combinado con el entorno educativo virtual o E-Learning.The teaching-learning process in the university academic environment in recent years has witnessed remarkable changes, starting with the implementation of the Internet in the classroom, in conjunction with various Web 2.0 tools, resulting teaching methods such as the Blended-learning and then the E-learning. To complement this, mobile e-learning appears or M-learning, which has been gaining momentum as the technology of mobile devices is growing both in the implementation of computational resources, such as bandwidth management thereof, added to the overcrowding in use within the academic community. This development has led, at present the management of information (voice, data and video), becomes increasingly through different types of mobile device, which has opened a whole range of applications in the academic and corporate, combined with the virtual learning environment or E-Learning

Public Capital and Regional Economic Growth: a SVAR Approach for the Spanish Regions

Recently, a significant share of the empirical analysis on the impact of public capital on regional growth has used multivariate time-series frameworks based on vector autoregressive (VAR) models. Nevertheless, not as much attention has been dedicated to the analysis of the long-run determinants of regional growth processes using multi-region panel data and applying panel integration and co-integration techniques. This paper estimates the dynamic domestic effects of public infrastructure using a structural vector autoregressive (S-VAR) methodology for the Spanish regions. From a methodological point of view, the paper contains several features that can be viewed as a contribution to the existing empirical literature. First, the important issues of the stationarity of the data and the existence and estimation of cointegrating relationships in the long-run are addressed in the context of the analysis of panel data. Secondly, the long-run cointegrating production function is embedded within structural vector error correction (S-VEC) shortrun models to produce consistent estimates of impulse responses, contrary to many researchers who have estimated unrestricted VAR models in levels or VAR models in first differences. The estimates reveal new results with respect to the previous empirical evidence

Community ecology and functional potential of bacteria, archaea, eukarya and viruses in Guerrero Negro microbial mat

In this study, the microbial ecology, potential environmental adaptive mechanisms, and the potential evolutionary interlinking of genes between bacterial, archaeal and viral lineages in Guerrero Negro (GN) microbial mat were investigated using metagenomic sequencing across a vertical transect at millimeter scale. The community composition based on unique genes comprised bacteria (98.01%), archaea (1.81%), eukarya (0.07%) and viruses (0.11%). A gene-focused analysis of bacteria archaea, eukarya and viruses showed a vertical partition of the community. The greatest coverages of genes of bacteria and eukarya were detected in first layers, while the highest coverages of genes of archaea and viruses were found in deeper layers. Many genes potentially related to adaptation to the local environment were detected, such as UV radiation, multidrug resistance, oxidative stress, heavy metals, salinity and desiccation. Those genes were found in bacterial, archaeal and viral lineages with 6477, 44, and 1 genes, respectively. The evolutionary histories of those genes were studied using phylogenetic analysis, showing an interlinking between domains in GN mat.NASA’s Exobiology Program. Ref. 17-EXO17-2-013

The AMIGA sample of isolated galaxies. IV. A catalogue of neighbours around isolated galaxies

Studies of the effects of environment on galaxy properties and evolution require well defined control samples. Such isolated galaxy samples have up to now been small or poorly defined. The AMIGA project (Analysis of the interstellar Medium of Isolated GAlaxies) represents an attempt to define a statistically useful sample of the most isolated galaxies in the local (z < 0.05) Universe. A suitable large sample for the AMIGA project already exists, the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973; 1050 galaxies), and we use this sample as a starting point to refine and perform a better quantification of its isolation properties. Digitised POSS-I E images were analysed out to a minimum projected radius R > 0.5 Mpc around 950 CIG galaxies (those within Vr = 1500 km s-1 were excluded). We identified all galaxy candidates in each field brighter than B = 17.5 with a high degree of confidence using the LMORPHO software. We generated a catalogue of approximately 54 000 potential neighbours (redshifts exist for 30% of this sample). Six hundred sixty-six galaxies pass and two hundred eighty-four fail the original CIG isolation criterion. The available redshift data confirm that our catalogue involves a largely background population rather than physically associated neighbours. We find that the exclusion of neighbours within a factor of four in size around each CIG galaxy, employed in the original isolation criterion, corresponds to Delta Vr ~ 18000 km s-1 indicating that it was a conservative limit. Galaxies in the CIG have been found to show different degrees of isolation. We conclude that a quantitative measure of this is mandatory. It will be the subject of future work based on the catalogue of neighbours obtained here.Comment: Accepted by A&A, 10 pages, 8 figures, 4 table

Asymptotic behaviour of the density in a parabolic SPDE

Consider the density of the solution $X(t,x)$ of a stochastic heat equation with small noise at a fixed $t\in [0,T]$, $x \in [0,1]$. In the paper we study the asymptotics of this density as the noise is vanishing. A kind of Taylor expansion in powers of the noise parameter is obtained. The coefficients and the residue of the expansion are explicitly calculated. In order to obtain this result some type of exponential estimates of tail probabilities of the difference between the approximating process and the limit one is proved. Also a suitable local integration by parts formula is developped.Malliavin Calculus, parabolic SPDE, large deviations, Taylor expansion of a density, exponential estimates of the tail probabilities, stochastic integration by parts formula