A Log-linear model of grain size influence on the geochemistry of sediments

Sediment composition is mainly controlled by the nature of the source rock(s), and chemical (weathering) and physical processes (mechanical crushing, abrasion, hydrodynamic sorting) during alteration and transport. Although the factors controlling these processes are conceptually well understood, detailed quantification of compositional changes induced by a single process are rare, as are examples where the effects of several processes can be distinguished. The present study was designed to characterize the role of mechanical crushing and sorting in the absence of chemical weathering. Twenty sediment samples were taken from Alpine glaciers that erode almost pure granitoid lithologies. For each sample, 11 grain-size fractions from granules to clay (ø grades <-1 to >9) were separated, and each fraction was analysed for its chemical composition. The presence of clear steps in the box-plots of all parts (in adequate ilr and clr scales) against ø is assumed to be explained by typical crystal size ranges for the relevant mineral phases. These scatter plots and the biplot suggest a splitting of the full grain size range into three groups: coarser than ø=4 (comparatively rich in SiO2, Na2O, K2O, Al2O3, and dominated by “felsic” minerals like quartz and feldspar), finer than ø=8 (comparatively rich in TiO2, MnO, MgO, Fe2O3, mostly related to “mafic” sheet silicates like biotite and chlorite), and intermediate grains sizes (4≤ø <8; comparatively rich in P2O5 and CaO, related to apatite, some feldspar). To further test the absence of chemical weathering, the observed compositions were regressed against three explanatory variables: a trend on grain size in ø scale, a step function for ø≥4, and another for ø≥8. The original hypothesis was that the trend could be identified with weathering effects, whereas each step function would highlight those minerals with biggest characteristic size at its lower end. Results suggest that this assumption is reasonable for the step function, but that besides weathering some other factors (different mechanical behavior of minerals) have also an important contribution to the trend. Key words: sediment, geochemistry, grain size, regression, step function

Statistical treatment of grain-size curves and empirical distributions: densities as compositions?

The preceding two editions of CoDaWork included talks on the possible consideration of densities as infinite compositions: Egozcue and D´ıaz-Barrero (2003) extended the Euclidean structure of the simplex to a Hilbert space structure of the set of densities within a bounded interval, and van den Boogaart (2005) generalized this to the set of densities bounded by an arbitrary reference density. From the many variations of the Hilbert structures available, we work with three cases. For bounded variables, a basis derived from Legendre polynomials is used. For variables with a lower bound, we standardize them with respect to an exponential distribution and express their densities as coordinates in a basis derived from Laguerre polynomials. Finally, for unbounded variables, a normal distribution is used as reference, and coordinates are obtained with respect to a Hermite-polynomials-based basis. To get the coordinates, several approaches can be considered. A numerical accuracy problem occurs if one estimates the coordinates directly by using discretized scalar products. Thus we propose to use a weighted linear regression approach, where all k- order polynomials are used as predictand variables and weights are proportional to the reference density. Finally, for the case of 2-order Hermite polinomials (normal reference) and 1-order Laguerre polinomials (exponential), one can also derive the coordinates from their relationships to the classical mean and variance. Apart of these theoretical issues, this contribution focuses on the application of this theory to two main problems in sedimentary geology: the comparison of several grain size distributions, and the comparison among different rocks of the empirical distribution of a property measured on a batch of individual grains from the same rock or sediment, like their composition

Educar en imatge, la por : de la rondalla a l'espot publicitari. 'Educar en imagen, el miedo : de la Rondalla al spot publicitario'.

Este artículo quiere justificar la necesidad de analizar la transmisión de la emoción a través del lenguaje, teniendo en cuenta el actual cambio social e individual que suponen los avances tecnológicos. En primer lugar cabe señalar que el cambio al que se hace referencia es el paso de una cultura trasmitida básicamente mediante la palabra y la letra impresa a una cultura trasmitida mediante la imagen. La lengua escrita es desplazada por la icónica. Este cambio en la comunicación entre individuos es también un cambio en la manera de pensar, de ser, de sentir. El artículo se centra en una emoción, el miedo. Se concluye afirmando que los avances tecnológicos proporcionan una nueva percepción del mundo, nuevas emociones y nuevos miedos, y que el lenguaje publicitario es actualmente más eficaz para suscitar emociones a más cantidad de personas que el lenguaje escrito. Se hace referencia especial a las Rondalles Mallorquines, escritas por Mossèn Alcover en el siglo XIX, y el papel que tuvieron para despertar la imaginación y las emociones del niño.

How do I set up my thesis so it meets the University's Page Setup regulations for paper size and margins?

This video shows how to ensure the document: • has mirror margins that alternate on left and right hand pages • is A4 in size • has margins that are in-line with the regulations • has its major sections starting on the right hand (odd numbered) page Although this video shows how to perform these tasks in Word 2010, they are virtually identical in Word 2013. In Word 2011 for Mac the steps are very similar and precise details can be found in the Word 2011 Sections manual.

Deletion Analysis of 15 exons located outside and inside a “Hot Spot” in the Duchenne Muscular Dystrophy gene in Duchenne’s Muscular dystrophy patients

Introduction. Duchenne and Becker Muscular Dystrophies (DMD/DMB) are X-linked recessive diseases characterized by progressive muscle weakness and wasting, loss of motor skills and death after the second decade of life. Deletions are the most prevalent mutations that affect the dystrophin gene, which spans 79 exons.Objective: Identify deletions on the dystrophin gene in 58 patients affected with DMD.Methods: Through multiplex PCR identify deletions on the dystrophin gene in 58 patients with DMD and observe the frequency of this mutation in our population.Results: We found deletions in 1.72% of patients (1 of 58 persons). Deletions were not the principal cause of disease in our population. It is possible that duplications and point mutations caused this illness in our patients.Conclusions: The frequency of deletions in the 15 exons analyzed from the dystrophin gene was low. The predominant types of mutation in our patients` samples were not deletions as has been observed in the literature worldwide, therefore, it is important to determine other types of mutations as are duplications and point mutations.

The Intrapreneur Innovation:Led by Medium and Small Size Companies‘Managers*(Qualitative Research)

This research is focused on an exploratory study developed with Pymes managers and theirroles as intrapreneurs. Using their leadership to impel innovation into organizations.Looking to determined how Pymes employers incentive into organizations individuals or groupinnovations. Therefore, it is possible to think that managers lead the innovation process, whichis classified gradually according to companies needs in order to improve their competitiveness.Organization must have intrapreneuring and organized culture with flexible structure to generateindividual autonomy. A characteristic is the amount of capital risk needed; that is why it isnecessary encourage their work and their risk tolerance.

The cyclical behavior of bank capital buffers in an emerging economy: size do matters

Using a panel of Colombian banks and quarterly data between 1996:1 and 2010:3, we study the relationship between short-run adjustemnts in bank capital buffers and the business cycle. We follow a partial adjustment framework and control for several variables that have been identified as important determinants of bank capital buffers in previous studies, and find that bank capital buffers vary over the business cycle. We are able to identify a negative co-movement of capital buffers and and the business cycle. However, we also find that capital buffers of small and large banks behave asymmetrically during the business cycle. While the former appear to be constant over time, once the appropriate set of control variables is used, the latter present a countercyclical behavior. Our results suggest the possible need of the implementation of regulatory policy measures in developing countries

Forecasting the spot prices of various coffee types using linear and non-linear error correction models

Este documento estima modelos lineales y no-lineales de corrección de errores para los precios spot de cuatro tipos de café. En concordancia con las leyes económicas, se encuentra evidencia que cuando los precios están por encima de su nivel de equilibrio, retornan a éste mas lentamente que cuando están por debajo. Esto puede reflejar el hecho que, en el corto plazo, para los países productores de café es mas fácil restringir la oferta para incrementar precios, que incrementarla para reducirlos. Además, se encuentra evidencia que el ajuste es más rápido cuando las desviaciones del equilibrio son mayores. Los pronósticos que se obtienen a partir de los modelos de corrección de errores no lineales y asimétricos considerados en el trabajo, ofrecen una leve mejoría cuando se comparan con los pronósticos que resultan de un modelo de paseo aleatorio.

Suministro de información y seguros de confiabilidad en el mercado SPOT de generación de electricidad colombiano.

Este artículo tiene como objetivo presentar algunos mecanismos de mercado que pueden inducir a mejorar la confiabilidad en el mercado de generación de electricidad spot colombiano; estos son:1) la provisión de información adicional al precio unitario spot, en un mercado que por su naturaleza es aleatorio, y 2) seguros de confiabilidad, al reconocerse que las demandas son altamente inflexibles. También se desarrolla una aplicación para mostrar cómo operarían en la práctica estos mecanismos y se determinan las restricciones que se deben corregir para que sean operativos. Este programa de seguros garantiza una confiabilidad eficiente, provee información importante para los agentes del mercado y reglas de asignación que minimizan los costos económicos en caso de fallas en la capacidad de generación de electricidad, que podrían ser aplicados a mercados de generación de electricidad como el colombiano, donde se han tenido recurrentes crisis de abastecimiento y se ha pensado profundizar en las reformas de este mercado.

1001 animals to spot.

El texto y las ilustraciones tienen por objeto ayudar a los niños de primaria a desarrollar habilidades como leer, contar, comparar e identificar. En cada doble página hay escenas de animales en diferentes ecosistemas del mundo, la selva, la montaña, el mar, el bosque, el Polo Norte. Alrededor de los márgenes de las páginas hay una lista de los animales que hay que buscar junto con el número de animales de este tipo que se encuentran en ese lugar. Otro juego se presenta casi al final del libro : En dibujos de Leo hay un grupo adicional de animales que este personaje pinta y el niño debe mirar hacia atrás para localizar las imágenes realizadas por Leo.

Spot goes splash! : and other stories.

Tres historias en las que se narra cómo Spot se divierte con sus amigos bajo la lluvia, va a al parque de atracciones con sus abuelos y, por último, tiene un ajetreado día en casa.

Spot visits his grandparents.

El perrito Spot va a visitar a sus abuelos y les ayuda a cuidar el jardín. Disfruta con las travesuras de Spot y levanta las solapas para jugar con él.

Spot's first walk.

Spot es aún un cachorro cuando su madre le envía a dar su primer paseo. Encuentra muchos animales y sorpresas debajo de las solapas.

Spot's windy day : and other stories.

Tres historias en las que Spot tiene una aventura con su cometa, husmeando encuentra la respuesta a un misterio, y las diversiones que tiene en un día nevado.

Where's Spot?

Es la hora de comer y el perrito Spot no aparece,su madre le busca por la casa, en el reloj, en el piano. Debajo de cada solapa hay una sorpresa divertida.