Variables de influencia en la productividad de biomasa de matorral en la mancomunidad de El Alto Jarama-Atazar

La situación energética actual, caracterizada por la búsqueda de nuevas fuentes de energía, sustitutivas de los combustibles fósiles tradicionales y menos agresivas con el medio ambiente, ha hecho necesaria la puesta en marcha de políticas y acuerdos a nivel mundial, que buscan reducir la contaminación y fomentar las energías renovables. La biomasa, recurso renovable perteneciente a cada país y con un poder calorífico suficientemente alto como para emplearse energéticamente, surge como alternativa a dichos combustibles fósiles. Estos aspectos han convertido el estudio del potencial biomásico de los montes en uno de los pasos previos imprescindibles para cualquier proyecto vinculado al desarrollo de las bioenergías. Sin embargo, la evaluación de la biomasa encierra numerosas dificultades, dado que como recurso vegetal y renovable que es, presenta un carácter variable, cualitativa y cuantitativamente. Este factor, junto a la complejidad de estimar el potencial biomásico de grandes extensiones, provoca que únicamente se calcule la biomasa arbórea, en detrimento de la arbustiva, proporcionando un valor generalmente más bajo del realmente disponible en cada zona. Este estudio establece una metodología más precisa para el cálculo de la biomasa potencial generada por el matorral, en una determinada zona de estudio (Mancomunidad de El Alto Jarama-Atazar).____________________________________The present situation in the energy field is mainly characterized by the constant search of new energy sources, traditional fossil fuel substitutive and less aggressive towards the environment. All this has favoured the implementation of policies and worldwide agreements to reduce pollution and to promote Renewable Energies. The Biomass, a renewable resource belonging to each country and with a sufficiently high heating value to use energetically, arises as an alternative to the above mentioned fossil fuels. These aspects have turned the study of the forestry biomass resources into one of the previous essential steps of any project related to the development of Bioenergy. However, Biomass quantifying has numerous difficulties given that as vegetable and as renewable resource, it presents a changeable character, both qualitatively and quantitatively. In addition the impossibility to estimate the Biomass potential in large extensions causes that only arboreal biomass to be calculated, to the detriment of the bush tree, and therefore, generally the estimation provides a value that is minor than the real one. This study tries to establish a more accurate methodology for the calculation of the potential Biomass generated by the thickets in a specific study zone (Mancomunidad de El Alto Jarama-Atazar)

A Methodology to Engineer and Validate Dynamic Multi-level Multi-agent Based Simulations

This article proposes a methodology to model and simulate complex systems, based on IRM4MLS, a generic agent-based meta-model able to deal with multi-level systems. This methodology permits the engineering of dynamic multi-level agent-based models, to represent complex systems over several scales and domains of interest. Its goal is to simulate a phenomenon using dynamically the lightest representation to save computer resources without loss of information. This methodology is based on two mechanisms: (1) the activation or deactivation of agents representing different domain parts of the same phenomenon and (2) the aggregation or disaggregation of agents representing the same phenomenon at different scales.Comment: Presented at 3th International Workshop on Multi-Agent Based Simulation, Valencia, Spain, 5th June 201

Counting Rotational Sets for Laminations of the Unit Disk from First Principles

By studying laminations of the unit disk, we can gain insight into the structure of Julia sets of polynomials and their dynamics in the complex plane. The polynomials of a given degree, $d$, have a parameter space. The hyperbolic components of such parameter spaces are in correspondence to rotational polygons, or classes of "rotational sets", which we study in this paper. By studying the count of such rotational sets, and therefore the underlying structure behind these rotational sets and polygons, we can gain insight into the interrelationship among hyperbolic components of the parameter space of these polynomials. These rotational sets are created by uniting rotational orbits, as we define in this paper. The number of such sets for a given degree $d$, rotation number $\frac pq$, and cardinality $k$ can be determined by analyzing the potential placements of pre-images of zero on the unit circle with respect to the rotational set under the $d$-tupling map. We obtain a closed-form formula for the count. Though this count is already known based upon some sophisticated results, our count is based upon elementary geometric and combinatorial principles, and provides an intuitive explanation.Comment: 12 pages, 5 figure

Electrocatalytic oxidation of ascorbic acid on mesostructured SiO2-conducting polymer composites

The conducting self-doping copolymer poly(aniline-co-ABA) preserves its redox activity at pH values as high as 7. This observation was the starting point to synthesize an organic inorganic hybrid composite able to electrochemically oxidize ascorbic acid molecules at that pH. The inorganic part of the catalytic element was an ordered mesoporous electrodeposit of SiO2, which has been used as the template for the electrochemical insertion of the self-doping copolymer. The oxidation of ascorbate ions at a fixed potential on this composite was studied by means of the kinetic model proposed by Bartlett and Wallace (2001). It was observed that the effective kinetic constant K-ME increased significantly but, simultaneously, k'(ME) remained almost constant when the composite was employed as the electrocatalytic substrate. These results were interpreted in the light of two combinations of kinetic constants, which strongly suggested that the increase in K-ME should be ascribed to the improvement in electronic conductivity of the copolymer induced by the highly ordered silica template. (C) 2015 Elsevier Ltd. All rights reserved.Financial support from the Spanish Ministerio de Economia y Competitividad and FEDER funds (MAT2013-42007-P), from the Generalitat Valenciana (PROMETE02013/038) and from the Fundacion Ramon Areces is gratefully acknowledged.Rivero, O.; Huerta, F.; Montilla, F.; Sanchis, C.; Morallón, E. (2015). Electrocatalytic oxidation of ascorbic acid on mesostructured SiO2-conducting polymer composites. European Polymer Journal. 69:201-207. https://doi.org/10.1016/j.eurpolymj.2015.06.004S2012076

Intrinsic Absorption in the Spectrum of NGC 7469: Simultaneous Chandra, FUSE, and STIS Observations

We present simultaneous X-ray, far-ultraviolet, and near-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 obtained with the Chandra X-Ray Observatory, the Far Ultraviolet Spectroscopic Explorer, and the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Previous non-simultaneous observations of this galaxy found two distinct UV absorption components, at -560 and -1900 km/s, with the former as the likely counterpart of the X-ray absorber. We confirm these two absorption components in our new UV observations, in which we detect prominent O VI, Ly alpha, N V, and C IV absorption. In our Chandra spectrum we detect O VIII emission, but no significant O VIII or O VII absorption. We also detect a prominent Fe K alpha emission line in the Chandra spectrum, as well as absorption due to hydrogen-like and helium-like neon, magnesium, and silicon at velocities consistent with the -560 km/s UV absorber. The FUSE and STIS data reveal that the H I and C IV column densities in this UV- and X-ray- absorbing component have increased over time, as the UV continuum flux decreased. We use measured H I, N V, C IV, and O VI column densities to model the photoionization state of both absorbers self-consistently. We confirm the general physical picture of the outflow in which the low velocity component is a highly ionized, high density absorber with a total column density of 10^20 cm^-2, located near the broad emission line region, although due to measurable columns of N V and C IV, we assign it a somewhat smaller ionization parameter than found previously, U~1. The high velocity UV component is of lower density, log N=18.6, and likely resides farther from the central engine as we find its ionization parameter to be U=0.08.Comment: Minor correction to abstract; STScI eprint #1683; 50 pages, incl. 19 figures, 4 tables; Accepted to Ap

An integrated model of work motivation applied in a multicultural sample

An integrated model of work motivation was tested in a multicultural sample by analyzing the construct and convergent validity of the measurement tools included in the HSA-Mot model. This model integrates within a relationship network a number of key motivational constructs that operate on different levels: needs, instrumentality, self-efficacy, equity and critical psychological states (knowledge of results, responsibility and meaningfulness). Two cross-sectional studies were conducted. The first concerned four different samples of employees from Chile, Spain, the United Kingdom and Portugal. The construct validity of the measurement tools was studied by means of a CFA. The second study, involving a sample of Mexican workers, analyzed the convergence between the motivational measures proposed by the integrated model and other measures of motivation. The results of both studies were positive and revealed high fit indices between the data and the proposed theoretical model (values above .90 and residuals below .08), as well as high convergence with the other measures used (correlations above .6). The HSA-Mot model shows correct index of validity in its measurement tools and, more importantly, provides key information for tailoring interventions once low levels of motivation have been detected

Temporary variation of Arachnofauna (Arachnida: Araneae) in a fragment of dry tropical forest (dtf) in the department of Atlántico, Colombia

Se analizó la variación temporal de la composición y estructura de la araneofauna en la Reserva Campesina La Montaña (RCM), departamento del Atlántico, Colombia. Se realizaron 10 muestreos entre noviembre de 2012 y agosto del 2013, con el fin de abarcar las épocas seca y de lluvias. Se delimitó un transecto lineal de 500 m de largo por 20 m de ancho, donde se marcaron 10 puntos de muestreo distanciados 50 m. En cada uno las arañas fueron capturadas empleando los métodos de captura manual (CM), agitación del follaje (AF), cernido de hojarasca (CH) y trampa de caída (TC). Se capturaron 1.866 individuos distribuidos en 32 familias, destacándose Araneidae como la más abundante con 525 individuos (28,1%), seguida por Salticidae y Lycosidae con 407 (21,8%) y 173 individuos (9,27%) respectivamente. La primera familia presentó su mayor abundancia en mayo (108), mientras que Salticidae presentó el mayor valor en enero (69) y Lycosidae en febrero con 33 individuos. Con respecto a la riqueza, los mayores valores se presentaron en junio (25) y diciembre con 22 familias. Adicionalmente, se registraron ocho gremios, de los cuales el más abundante (567 individuos) fue las constructoras de telas orbiculares (CTO), presentándose el mayor valor en mayo; mientras que las cursoriales del suelo (CS) fueron las más diversas (10 familias), siendo enero, febrero y junio los meses con mayor (8) número de familias. Estos resultados demuestran que las comunidades de arañas en la zona presentan un patrón temporal que depende de los cambios estacionales que se dan en el Bosque Seco Tropical.The temporary variation of the composition and structure of arachnofauna in the Reserva Campesina La Montaña (RCM), department of Atlántico, Colombia was analyzed. Ten samples were taken between November 2012 and August 2013 in order to cover the dry and rainy seasons. A 500 m long, 20 m wide linear transect was delimited, where 10 sampling points spaced 50 m from each other were marked. In each sampling point, spiders were collected using manual capture methods (MC), agitation foliage (AF), litter sifting (LS) and pitfall trap (PT). A total of 1,866 individuals distributed in 32 families were captured. The family Araneidae was the most abundant with 525 individuals (28.1%), followed by Salticidae and Lycosidae with 407 (21.8%) and 173 individuals (9.27%) respectively. The first family showed its greater abundance in May (108), while Salticidae showed the highest value in January (69) and Lycosidae in February with 33 individuals. With regard to the family richness, the highest values occurred in June (25) and December with 22 families recorded. Additionally eight guilds were observed from which the most abundant (567 individuals) were the orb weaving (OW) constructors, with the highest value in May while cursorial soil spiders (CS) were the most diverse (10 families), being January, February and June the months with the greatest number of families (8). These results demonstrate that the spider communities in the area present a temporal pattern that depends on seasonal changes that occur in the Dry Tropical Forest

An Aggregate Stochastic Model Incorporating Individual Dynamics for Predation Movements of Anelosimus Studiosus

In this paper, we discuss methods for developing a stochastic model which incorporates behavior differences in the predation movements of Anelosimus studiosus (a subsocial spider). Stochastic models for animal movement and, in particular, spider predation movement have been developed previously; however, this paper focuses on the development and implementation of the necessary mathematical and statistical methods required to expand such a model in order to capture a variety of distinct behaviors. A least squares optimization algorithm is used for parameter estimation to fit a single stochastic model to an individual spider during predation resulting in unique parameter values for each spider. Similarities and variations between parameter values across the spiders are analyzed and used to estimate probability distributions for the variable parameter values. An aggregate stochastic model is then created which incorporates the individual dynamics. The comparison between the optimal individual models to the aggregate model indicate the methodology and algorithm developed in this paper are appropriate for simulating a range of individualistic behaviors

FTIR-ATR Spectroscopy Combined with Multivariate Regression Modeling as a Preliminary Approach for Carotenoids Determination in Cucurbita spp

Quantitative analysis of carotenoids has been extensively reported using UV\u2010Vis spectrophotometry and chromatography, instrumental techniques that require complex extraction protocols with organic solvents. Fourier transform infrared spectroscopy (FTIR) is a potential alternative for simplifying the analysis of food constituents. In this work, the application of FTIR with attenuated total reflectance (ATR) was evaluated for the determination of total carotenoid content (TCC) in Cucurbita spp. samples. Sixty\u2010three samples, belonging to different cultivars of butternut squash (C. moschata) and pumpkin (C. maxima), were selected and analyzed with FTIR\u2010 ATR (attenuated total reflectance). Three different preparation protocols for samples were followed: homogenization (A), freeze\u2010drying (B), and solvent extraction (C). The recorded spectra were used to develop regression models by Partial Least Squares (PLS), using data from TCC, determined by UV\u2010Vis spectrophotometry. The PLS regression model obtained with the FTIR data from the freeze\u2010dried samples, using the spectral range 920\u20133000 cm 121, had the best figures of merit (R2CAL of 0.95, R2PRED of 0.93 and RPD of 3.78), being reliable for future application in agriculture. This approach for carotenoid determination in pumpkin and squash avoids the use of organic solvents. Moreover, these results are a rationale for further exploring this technique for the assessment of specific carotenoids in food matrices